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Title: Physiological economy in nutrition, with special reference to the minimal proteid requirement of the healthy man

Author: R. H. Chittenden

Release date: November 28, 2022 [eBook #69439]

Language: English

Credits: Mark C. Orton and the Online Distributed Proofreading Team at https://www.pgdp.net (This file was produced from images generously made available by The Internet Archive)

*** START OF THE PROJECT GUTENBERG EBOOK PHYSIOLOGICAL ECONOMY IN NUTRITION, WITH SPECIAL REFERENCE TO THE MINIMAL PROTEID REQUIREMENT OF THE HEALTHY MAN ***

[i]

PHYSIOLOGICAL ECONOMY
IN
NUTRITION

WITH SPECIAL REFERENCE TO THE MINIMAL
PROTEID REQUIREMENT OF THE
HEALTHY MAN

AN EXPERIMENTAL STUDY

BY
RUSSELL H. CHITTENDEN,
Ph.D., LL.D., Sc.D.

DIRECTOR OF THE SHEFFIELD SCIENTIFIC SCHOOL OF YALE UNIVERSITY
AND PROFESSOR OF PHYSIOLOGICAL CHEMISTRY; MEMBER OF THE
NATIONAL ACADEMY OF SCIENCES; PRESIDENT OF THE
AMERICAN PHYSIOLOGICAL SOCIETY; MEMBER OF
THE AMERICAN PHILOSOPHICAL SOCIETY, ETC.

NEW YORK
FREDERICK A. STOKES COMPANY
1907

[ii]

Copyright, 1904,
By Frederick A. Stokes Company

Published in November, 1904

THE UNIVERSITY PRESS, CAMBRIDGE, U. S. A.


[iii]

LIST OF ILLUSTRATIONS

Facing page
Group of soldiers at work in the Gymnasium 136
Side view of Fritz 198
Back view of Fritz 204
Front view of Coffman and Steltz 212
Back view of Coffman and Steltz 220
Side view of Zooman and Cohn 234
Back view of Zooman and Cohn 240
Side view of Loewenthal and Morris 258
Group of soldiers exercising in the Gymnasium 262
Front view of Sliney 272
Soldiers exercising in the Gymnasium 284
Soldiers exercising in the Gymnasium 296
Side view of Stapleton 328
Back view of Stapleton 366
Front view of W. L. Anderson and Bellis 440
Back view of W. L. Anderson and Bellis 442

[iv]


[v]

ACKNOWLEDGMENTS
OF FINANCIAL AID IN MEETING THE EXPENSE OF THE EXPERIMENTS HEREIN DESCRIBED

The writer has been most generously aided by substantial grants from the Bache Fund of the National Academy of Sciences, and from the Carnegie Institution of Washington; also by large donations from Mr. Horace Fletcher of Venice, and from Mr. John H. Patterson of Dayton, Ohio. In addition, the War Department of the United States met in large measure the expense of maintaining at New Haven the Detachment of Volunteers from the Hospital Corps of the United States Army, detailed here through the courtesy of Surgeon-General Robert Maitland O’Reilly.

ACKNOWLEDGMENTS
OF AID IN THE CONDUCT OF THE EXPERIMENTS

The successful carrying out of the experiments in all their details, especially the chemical work, has been rendered possible by the active and continuous co-operation of the writer’s colleague, Lafayette B. Mendel, Ph.D., Professor of Physiological Chemistry in the Sheffield Scientific School.

Efficient aid in the routine chemical and other work of the laboratory in connection with the experiments has been rendered by Frank P. Underhill, Ph.D., Arthur L. Dean, Ph.D., Harold C. Bradley, B.A., Robert B. Gibson, Ph.B., Oliver E. Closson, Ph.B., and Charles S. Leavenworth, Ph.B.

Dr. William G. Anderson, Director of the Yale Gymnasium, with the co-operation of his assistants, has rendered valuable aid in looking after the physical development of the men[vi] under experiment, in arranging for frequent strength tests, as well as in prescribing the character and extent of their work in the Gymnasium. The greater portion of the training of the soldiers was under the personal supervision of William H. Callahan, M.D., Medical Assistant at the Gymnasium, while Messrs. William Chase, Anton Muller, John Stapleton, and H. R. Gladwin, Assistant Instructors in the Gymnasium, led the drills and looked after the actual muscular training of the men.

In the study of “Reaction Time” and other matters of psychological interest the work was under the direction of Charles H. Judd, Ph.D., in charge of the Yale Psychological Laboratory, aided by Warren M. Steele, B.A., and Cloyd N. McAllister, Ph.D.

In the morphological study of the blood, etc., Dr. Wallace DeWitt, Lieutenant in command of the Army detail, rendered valuable aid. Dr. DeWitt likewise co-operated in all possible ways during his stay in New Haven to maintain the integrity of the conditions necessarily imposed on the soldier detail in an experiment of this character.

Further, acknowledgments are due the several non-commissioned officers of the Hospital Corps for their intelligent co-operation and interest. Finally, to the men of the Hospital Corps who volunteered for the experiment, our thanks are due for their cheerful compliance with the many restrictions placed upon them during their six months’ sojourn in New Haven, and for the manly way in which they conducted themselves under conditions not always agreeable.

To the students of the University who volunteered as subjects of experiment our acknowledgments are due for their intelligent co-operation, keen interest, and hearty compliance with the conditions imposed.


[vii]

PREFACE

There is no subject of greater physiological importance, or of greater moment for the welfare of the human race, than the subject of nutrition. How best to maintain the body in a condition of health and strength, how to establish the highest degree of efficiency, both physical and mental, with the least expenditure of energy, are questions in nutrition that every enlightened person should know something of, and yet even the expert physiologist to-day is in an uncertain frame of mind as to what constitutes a proper dietary for different conditions of life and different degrees of activity. We hear on all sides widely divergent views regarding the needs of the body, as to the extent and character of the food requirements, contradictory statements as to the relative merits of animal and vegetable foods; indeed, there is great lack of agreement regarding many of the fundamental questions that constantly arise in any consideration of the nutrition of the human body. Especially is this true regarding the so-called dietary standards, or the food requirements of the healthy adult. Certain general standards have been more or less widely adopted, but a careful scrutiny of the conditions under which the data were collected leads to the conclusion that the standards in question have a very uncertain value, especially as we see many instances of people living, apparently in good physical condition, under a régime not at all in harmony with the existing standards.

Especially do we need more definite knowledge of the true physiological necessities of the body for proteid or albuminous foods, i. e., those forms of foods that we are accustomed to speak of as the essential foods, since they are absolutely requisite for life. If our ideas regarding the daily quantities of these foods necessary for the maintenance of health and[viii] strength are exaggerated, then a possible physiological economy is open to us, with the added possibility that health and vigor may be directly or indirectly increased. Further, if through years and generations of habit we have become addicted to the use of undue quantities of proteid foods, quantities way beyond the physiological requirements of the body, then we have to consider the possibility that this excess of daily food may be more or less responsible for many diseased conditions, which might be obviated by more careful observance of the true physiological needs of the body.

First, however, we must have more definite information as to what the real necessities of the body for proteid food are, and this information can be obtained only by careful scientific experimentation under varying conditions. This has been the object of the present study, and the results obtained are now placed before the public with the hope that they will prove not only of scientific interest and value, but that they will also serve to arouse an interest in the minds of thoughtful people in a subject which is surely of primary importance for the welfare of mankind. That the physical condition of the body exercises an all-powerful influence upon the mental state, and that a man’s moral nature even is influenced by his bodily condition are equally certain; hence, the subject of nutrition, when once it is fully understood and its precepts obeyed, bids fair to exert a beneficial influence not only upon bodily conditions, but likewise upon the welfare of mankind in many other directions.

In presenting the results of the experiments, herein described, the writer has refrained from entering into lengthy discussions, preferring to allow the results mainly to speak for themselves. They are certainly sufficiently convincing and need no superabundance of words to give them value; indeed, such merit as the book possesses is to be found in the large number of consecutive results, which admit of no contradiction and need no argument to enhance their value. The results presented are scientific facts, and the conclusions they justify are self-evident.


[ix]

CONTENTS

Page
Acknowledgments v
Preface vii
Introductory 1
I.
Experiments with Professional Men.
Chittenden: Daily Record of Nitrogen Excretion, etc. 24
First Nitrogen Balance, with comparison of income and output, amount and character of the daily food 34
Second Nitrogen Balance, with composition of daily food, etc. 43
Mendel: Daily Record of Nitrogen Excretion, etc. 53
First Nitrogen Balance, with comparison of income and output, amount and character of the daily food 60
Second Nitrogen Balance, with composition of daily food, etc. 67
Underhill: Daily Record of Nitrogen Excretion, etc. 79
First Nitrogen Balance, with comparison of income and output, composition of the daily food, etc. 87
Second Nitrogen Balance, with composition of daily food, etc. 93
Dean: Daily Record of Nitrogen Excretion, etc. 98
Nitrogen Balance, with comparison of income and output, amount and character of the daily food 103
Beers: Daily Record of Nitrogen Excretion, etc. 111
First Nitrogen Balance, with comparison of income and output, amount and character of the daily food 114
Second Nitrogen Balance, with composition of daily food, etc. 121
Summary of Results; True Proteid Requirements 127
II.
Experiments with Volunteers from the Hospital Corps of the United States Army.
Description of the Men 134
Daily Routine of Work 135[x]
Daily Record of Nitrogen Excretion, etc., for each of the thirteen men under experiment 139
Average Daily Output of Nitrogen 199
Nitrogen Metabolized per kilo of Body-Weight 201
Changes in Body-Weight during the Experiment 202
First Nitrogen Balance, with comparison of income and output, amount and character of the daily food 203
Second Nitrogen Balance, with composition of daily food, etc. 223
Third Nitrogen Balance, with composition of daily food, etc. 242
Summary regarding Nitrogen Requirement 254
Physical Training of the Men—Report by Dr. Anderson of the Yale Gymnasium 255
Body Measurements 261
Strength or Dynamometer Tests 262
Comparison of the Total Strength of the Men at the beginning and end of the Experiment 274
Reaction Time Experiments—Report by Dr. Judd of the Yale Psychological Laboratory 276
Character and Composition of the Blood 283
General Conclusions 285
Daily Dietary of the Soldier Detail 288
III.
Experiments with University Students, trained in Athletics.
Consumption of Proteid Food by Athletes 327
Description of the Men 329
Daily Record of Nitrogen Excretion, etc., for each of the eight men under Experiment 332
Average Daily Excretion of Metabolized Nitrogen 364
Metabolized Nitrogen per kilo of Body-Weight 365
Daily Diet Prescribed 366
Nitrogen Balance, with comparison of income and output, and amount and character of the daily food, etc. 375
The Physical Condition of the Men 434
Strength or Dynamometer Tests 436
Report by Dr. Anderson of the Yale Gymnasium 439
Reaction Time—Report by Dr. Judd of the Yale Psychological Laboratory 442
General Summary; True Physiological Requirements for Proteid Food 454[xi]
IV.
The Systemic Value of Physiological Economy in Nutrition.
Diseases due to Perversion of Nutrition 455
Waste Products of Proteid Metabolism may be Dangerous to Health 456
Origin and Significance of Uric Acid 458
Modification of Uric Acid Excretion by diminishing the amount of Proteid Food 463
Tables showing Excretion of Uric Acid by the three groups of men under observation; Uric Acid per kilo of Body-Weight, etc. 467
V.
Economic and Sociological Importance of the Results 471
VI.
General Conclusions 474
VII.
Description of Illustrations 477

[1]

PHYSIOLOGICAL ECONOMY
IN NUTRITION

INTRODUCTORY

Note.—For the benefit of lay readers, metabolism, a word frequently made use of, may be defined as a term applied to the collective chemical changes taking place in living matter. When these metabolic changes are constructive, as in the building up of tissue protoplasm from the absorbed food material, they are termed anabolic; when they are destructive, as in the breaking down of living matter or in the decomposition of the materials stored up in the tissues and organs, they are termed katabolic. Proteid metabolism, or more exactly proteid katabolism, therefore, means the destructive decomposition of proteid or albuminous matter in the living body and is practically synonymous with nitrogenous metabolism, since the entire nitrogen income is mainly supplied by the proteids or albuminous matters of the food. The chief carbon income, on the other hand, is supplied by fats and carbohydrates, such as starches and sugars.

As the result of many years of observation and experiment certain general conclusions have been arrived at regarding the requisite amounts of food necessary for the maintenance of health and strength. Certain dietary standards have been set up which have found more or less general acceptance in most parts of the civilized world; standards which have been reinforced and added to by man’s aptitude for self-indulgence. Carl Voit, of Munich, whose long and successful life as a student of Nutrition renders his conclusions of great value, considers that an adult man of average body-weight (70-75 kilos) doing moderate muscular work requires daily 118 grams of proteid or albuminous food, of which 105 grams should be absorbable, 56 grams of fat, and 500 grams of carbohydrate, with a total fuel value of over 3000 large calories, in order to maintain the body in equilibrium. The Voit standard or daily diet is accepted more or less generally as representing the needs of the body under normal conditions of life, and[2] the conclusions arrived at by other investigators along these same lines have been more or less in accord with Voit’s figures. In confirmation of this statement the following data may be quoted:

AVERAGE DIETS.

Moleschott. Ranke.[1] Forster. Hultgren[2] and Landergren. Atwater. Studemund.[3] Schmidt.[4]
grams grams grams grams grams grams grams
Proteid 130 100 131 134 125 114 105
Carbohydrates 550 240 494 523 400 551 541
Fats 40 100 68 79 125 54 63
Fuel value (calories)[5] 3160 2324 3195 3436 3315 3229 3235

In many of these diets it is to be noted that the proteid requirement is placed at even a higher figure than Voit’s standard. Similarly, Erisman, studying the diets of Russian workmen having a free choice of food and doing moderately hard work, found the daily diet to be composed of 131.8 grams of proteid, 79.7 grams of fat, and 583.8 grams of carbohydrate, with a total fuel value of 3675 large calories. Further, Hultgren and Landergren[6] found that Swedish laborers doing hard work had as their daily diet 189 grams of proteid, 110 grams of fat, and 714 grams of carbohydrate, with a total fuel value of 4726 large calories. Voit found that German soldiers on active service consumed daily 145 grams of proteid, 100 grams of fat, and 500 grams of carbohydrate, with a total fuel value[3] of 3574 large calories. Lichtenfelt,[7] studying the nutrition of Italians, states that an Italian laborer doing a moderate amount of work requires 110.5 grams of proteid and a total fuel value for the daily food of 2698 calories, while at hard labor he needs 146 grams of proteid daily, with carbohydrates and fat sufficient to give 3088 large calories. In our own country Atwater,[8] who has made many valuable observations upon the dietetic habits of different classes of people and under different conditions of life, has stated that a somewhat more liberal allowance of proteid would seem desirable, say 125 grams, with a total fuel value of 3500 large calories for a man doing severe muscular labor.

In what is perhaps the latest book on alimentation, Armand Gautier,[9] writing of the French people, states that the ordinary man in that climate needs daily 110 grams of albuminous food, 68 grams of fat, and about 423 grams of amylaceous or saccharine food. It is possible, however, says Gautier, that the quantity of albuminous food can be reduced, if necessary, to 78 grams per day in case a man is not doing work and takes in addition at least 50 grams of fat and 485 grams of carbohydrate food. Where, however, an individual works eight to ten hours a day, the ration, says Gautier, must be increased to at least 135 grams of albuminous food, with 85 to 100 grams of fat, and with from 500 to 900 grams of starchy food.

While these figures may be taken as showing quite conclusively the dietetic standards adopted by mankind, there is no evidence whatever that they represent the real needs or requirements of the body. We may even question whether simple observation of the kinds and amounts of food consumed by different classes of people under different conditions of life have any very important bearing upon this question. They[4] throw light upon dietetic habits, it is true, but such observations give no information as to how far the diets in question serve the real needs of the body. We may find, for example, that under certain given conditions of diet the people in question have the appearance of being well nourished, and that they do their work with apparent ease and comfort; but might not these same results follow with smaller amounts of food? If so, there must of necessity be a certain amount of physiological economy under the more restricted diet, and a consequent ultimate gain to the body through diminished wear and tear of the bodily machinery.

Indeed, experimental work and observations scattered through the last few years have suggested the possibility of much lower standards of diet sufficing to meet the real physiological needs of the body. Thus, Hirschfeld,[10] in 1887, found in experimenting on himself (24 years of age and weighing 73 kilos) that it was possible to maintain nitrogen equilibrium on a diet containing only 5 to 7.5 grams of nitrogen per day, or 35 to 45 grams of proteid, for a period of ten to fifteen days. The amount of non-nitrogenous food consumed, however, was fairly large, especially the amount of butter,—frequently 100 grams a day—the average fuel value ranging from 3750 to 3916 large calories daily. In 1888 Hirschfeld,[11] again experimenting on himself, maintained nitrogen equilibrium for several days on 7.5 grams of nitrogen per day, with fats and carbohydrate sufficient to yield a total fuel value of 3462 large calories as the daily average. The chief criticism of Hirschfeld’s experiments is that he failed to obtain in all cases definite analytical data of the food-stuffs employed and failed to determine the nitrogen of the fæces. Still his results are of value as indicating the possibility of maintaining nitrogenous equilibrium for a brief time at least on a low proteid intake.

[5]

Kumagawa,[12] studying especially the diet of the Japanese and experimenting on himself (27 years old and weighing 48 kilos), found with a purely vegetable diet, containing per day 54.7 grams of proteid, 2.5 grams of fat, and 569.8 grams of carbohydrate, that he showed for a period of nine days a plus balance of nitrogen, indicating that his body was laying on about 4 grams of proteid per day. The nitrogen excreted per urine and fæces amounted to 8.09 grams per day, while the nitrogen in the daily food amounted to 8.75 grams. It is interesting to observe in these experiments, as indicating the degree of absorption of the vegetable food (composed in large measure of rice) that the daily average of nitrogen in the urine amounted to 6.069 grams and in the fæces 2.029 grams. In other words, of the 54.7 grams of nitrogen-containing food only 37.8 grams were absorbed, 12.69 grams passing out with the fæces. The total fuel value of the absorbed food per day was 2478 large calories. Similarly, Hirschfeld[13] has called attention to the fact that with many vegetable foods especially, not more than 75 per cent of the ingested proteid can be digested and absorbed, thus emphasizing the necessity of paying heed to the character of the proteid food in considering the nutritive value of a given diet.

In some experiments reported by C. Voit[14] in 1889, on the diet of vegetarians, E. Voit and Constantinidi found that nitrogenous equilibrium was established in one man with about 8 grams of nitrogen, corresponding to 48.5 grams of proteid as the daily diet, with large amounts of starchy foods and some fat. Similarly, Nakahama[15] in the same year, studying the diet (mostly vegetable) and nutritive condition of thirteen German laborers in Leipzig, found that their daily[6] food contained on an average 85 grams of proteid, but Carl Voit criticising these results states that the men were of comparatively light body-weight—about 60 kilos—and not well nourished.

Kellner and Mori,[16] studying the nutrition of a Japanese (weighing 52 kilos and 23 years of age) state that on a purely vegetable diet containing 11.34 grams of nitrogen, of which only 8.58 grams were digested, there was a distinct loss of body-weight, with a daily loss to the body of 1.16 grams of nitrogen. On a mixed diet, however, containing fish, it was possible to establish nitrogenous equilibrium with a daily diet containing 17.48 grams of nitrogen, of which 15.27 grams were digested and utilized. Similarly, Caspari,[17] 29 years old and weighing 66.2 kilos, found that while he could maintain his body in nitrogenous equilibrium on 13.26 grams of nitrogen per day, he could not accomplish it on 10.1 grams of nitrogen, though his daily food contained 3200 large calories.

Other investigators, however, have found no great difficulty in establishing nitrogenous equilibrium in man with much lower quantities of proteid food. Thus, Klemperer[18] found in the case of two young men of 64 and 65.5 kilos body-weight respectively, in an experiment lasting eight days, that nitrogenous equilibrium was established on 4.38 and 3.58 grams of nitrogen per day, but with a daily diet containing in addition to the small amount of proteid 264 grams of fat, 470.4 grams of carbohydrate, and 172 grams of alcohol, with a total fuel value of 5020 large calories.

Peschel,[19] too, has reported experimental results showing that he was able to establish nitrogenous equilibrium for a[7] brief period with 7 grams of nitrogen daily, 5.31 grams appearing in the urine and 1.58 grams in the fæces.

Caspari and Glaessner,[20] in a five-days’ experiment with two vegetarians, found that the wife consumed daily, on an average, 5.33 grams of nitrogen, with fats and carbohydrates to equal 2715 calories, while the man took in 7.82 grams of nitrogen and 4559 calories. Both persons laid on nitrogen in spite of the low intake of proteid food.

Siven’s[21] experiments, however, are perhaps worthy of more careful consideration. Of 60 kilos body-weight and 30½ years of age, his experiments conducted on himself extended through thirty-two days with establishment of nitrogenous equilibrium on 6.26 grams of nitrogen. Moreover, in another experiment he was in nitrogen equilibrium for a day or two at least on 4.5 grams of nitrogen. In Siven’s experiment, the most noticeable feature is the added fact that the total intake of food per day was comparatively low, with a fuel value of only 2444 large calories. In this connection we may call attention to the recent experiments of Landergren,[22] who found with four individuals fed on a daily diet containing only 2.1 to 2.4 grams of nitrogen, but with a large amount of carbohydrate, some fat and alcohol, that on the fourth day of this “specific nitrogen hunger” only 3 to 4 grams of nitrogen were metabolized and appeared in the urine. In other words, a healthy adult man having a sufficient intake of non-nitrogenous food seemingly need not metabolize more proteid than suffices to yield 3 to 4 grams of nitrogen per day.

Such data as these, of which many more might be quoted, surely warrant the question, how far are we justified in assuming the necessity for the rich proteid diet called for by the Voit standard? Voit, however, with many other physiologists[8] would apparently object to any diminution of the daily 118 grams of proteid for the moderate worker, on the ground that an abundance of proteid in the food is a necessity for the maintenance of physical vigor and muscular activity. This view is certainly reinforced by the customs and habits of mankind; but we may well query whether our dietetic habits will bear criticism, and in the light of modern scientific inquiry we may even express doubt as to whether a rich proteid diet adds anything to our muscular energy or bodily strength.

How far can our natural instinct be trusted in the choice of diet? We are all creatures of habit, and our palates are pleasantly excited by the rich animal foods with their high content of proteid, and we may well question whether our dietetic habits are not based more upon the dictates of our palates than upon scientific reasoning or true physiological needs. There is a prevalent opinion that to be well nourished the body must have a large excess of fat deposited throughout the tissues, and that all bodily ills and weaknesses are to be met and combated by increased intake of food. There is constant temptation to increase the daily ration, and there is almost universal belief in the efficacy of a rich and abundant diet to strengthen the body and to increase bodily and mental vigor. Is there any justification for these beliefs? None, apparently, other than that which comes from the customs of generations of high living.

It is self-evident that the smallest amount of food that will serve to keep the body in a state of high efficiency is physiologically the most economical, and hence the best adapted for the needs of the organism. Any excess over and above what is really needed is not only uneconomical, but may be directly injurious. This is especially true of the proteid or albuminous foods. It is, however, quite proper to question whether a brief experiment of a few days in which nitrogenous equilibrium is perhaps established at the low level of 4 to 5 grams of nitrogen, the equivalent of 25 to 35 grams of proteid, is to be accepted as fixing the daily requirements of the healthy man, offsetting the customs or habits of a lifetime. Voit himself,[9] however, has clearly emphasized the general principle that the smallest amount of proteid, with non-nitrogenous food added, that will suffice to keep the body in a state of continual vigor is the ideal diet. Proteid decomposition products are a constant menace to the well-being of the body; any quantity of proteid or albuminous food beyond the real requirements of the body may prove distinctly injurious. We see the evil effects of uric acid in gout, but there are many other nitrogenous waste products of proteid katabolism, which with excess of proteid food are liable to be unduly conspicuous in the fluids and tissues of the body, and may do more or less damage prior to their excretion through the kidneys. Further, it requires no imagination to understand the constant strain upon the liver and kidneys, to say nothing of possible influence upon the central and peripheral parts of the nervous system, by these nitrogenous waste products which the body ordinarily gets rid of as speedily as possible. They are an ever present evil, but why increase them unnecessarily? This question brings us back to the starting-point. What is the minimal proteid requirement for the healthy man, or rather, how far can we safely and advantageously diminish our proteid intake below the commonly accepted standards?

The question of safety is a pertinent one. Thus, Munk[23] some years ago (1893) sounded a warning on this point which was later confirmed by Rosenheim.[24] Both of these observers reported that in dogs fed for some time on a low proteid diet, but with an abundance of carbohydrate and fat, there was after some weeks (6-8) a loss of the power of absorption from the alimentary tract, dependent not alone upon a changed condition of the epithelial cells of the intestine, but also upon a diminished secretion of the digestive juices, loss of body-weight, strength, and vigor, followed speedily by death. If[10] these results were really due to the low proteid diet, they suggest a grave danger which must not be lightly passed by. Jägerroos[25] has likewise observed, experimenting on dogs, that there was, after some months, a striking disturbance of the intestines on a low proteid intake, which, however, was eventually traced to a distinct infection, and probably in no manner connected with the diminished amount of proteid in the diet. In these various experiments on dogs carried out by Munk, Rosenheim, and by Jägerroos, there was of necessity great monotony in the diet, and in Munk’s experiments no fresh meat at all was fed, but simply dried food. In other words, if the diet was in any sense responsible for the poor health of the animals, it is fully as plausible to attribute the results to the abnormal conditions under which the animals were kept as to any specific effect due to the low proteid intake. It is very essential that the food of dogs, as of men, shall fulfil all ordinary hygienic conditions. It must be not only of sufficient quantity for the true needs of the body, but it should also have the necessary variety with reasonable degree of digestibility, and proper volume or bulk. When these qualities are lacking, it is not strange if deviations from the normal gradually develop. That the low intake of proteid food could be responsible for the condition existing in Munk’s and Rosenheim’s experiments is not plausible; a view which is strongly reinforced by many observations, notably those of Albu[26] on a woman thirty-seven years old and weighing 37.5 kilos, who had followed a vegetarian diet for six years, and who while under Albu’s care for two years consumed only 34 grams of proteid per day, the total fuel value of the food being only 1400 calories per day. This woman was in nitrogenous equilibrium on 5.4 grams of nitrogen, and on this diet had freed herself from the illness to which she had long been subject.

[11]

Voit’s[27] vegetarian is described by Voit himself as a man twenty-eight years old, weighing 57 kilos, well nourished, with well developed muscles, etc. He had lived on a purely vegetable diet for three years, and was found to be in nitrogenous equilibrium on 8.2 grams of nitrogen. No mention is made of any disagreeable effects connected with this low proteid ration, although persisted in for several years. Jaffa’s[28] experiments and observations on the fruitarians and nutarians of California “showed in every case (two women and three children) that though the diet had a low protein and energy value, the subjects were apparently in excellent health and had been so during the five to eight years they had been living in this manner.” In comparing the income and outgo of nitrogen on a diet composed mainly of nuts and fruits, it was observed in two subjects that 8 grams of nitrogen were sufficient to bring about nitrogen equilibrium, while with two other subjects on a like diet the nitrogen required daily for equilibrium was about 10 grams. The diet used in these experiments, however, was of necessity more or less restricted in variety, and was without doubt somewhat monotonous. Jaffa appears to agree with Caspari that the minimum amount of proteid required daily varies with the individual, and may even vary with the same individual at different times. Further, Jaffa, in harmony with Siven, believes that after the body has suffered a loss of nitrogen, there is at once an effort to attain nitrogenous equilibrium, and that any gain of nitrogenous body material is a comparatively slow process. If this is true, it is obvious that the living substance of the tissue protoplasm must be slowly formed from the proteid of the diet. This, says Jaffa, should serve as a warning to anyone contemplating any appreciable decrease in the proteid of the daily diet.

Another statement made by Jaffa may be quoted in this[12] connection, since it illustrates the attitude taken by many physiologists on this question. “Even if it could be proved,” says Jaffa, “by a large number of experiments that nitrogen equilibrium can be maintained on a small amount of protein, it would still be a great question whether or not it would be wise to do so. There must certainly be a constant effort on the part of the human organism to attain this condition, and with a low protein supply it might be forced to do so under conditions of strain. In such a case the bad results might be slow in manifesting themselves, but might also be serious and lasting. It has also been suggested that when living at a fairly high protein level the body is more resistant to disease and other strains than when the protein level is low.” While these suggestions demand careful consideration, it is equally evident that there is another side to the question, viz., the possible danger to the body from the physiological action of the larger amounts of nitrogenous waste products which result from an excess of proteid food, and which float about through the system prior to their excretion. In addition, we must not overlook the great loss of energy to the body in handling and getting rid of the surplus of unnecessary food of whatever kind introduced into the alimentary tract, to say nothing of the danger of intestinal putrefaction and toxæmia when from any cause the system loses its ability to digest and absorb the excess of food consumed. Further, the possible strain on the kidneys and other organs must not be overlooked. Hence we may well query on which side lies the greater danger. To an unprejudiced observer, one not wedded to old-time tradition, it would seem as if great effort was being made to sustain the claims of a high-proteid intake. It is surely well to be careful, but it is certainly not necessary to magnify imaginary dangers to the extent of suppressing all efforts toward the establishment of possible physiological economy.

In a paper read before the Physiological Section of the British Medical Association in 1901 by Dr. van Someren, claim is made of the existence of a reflex of deglutition, the proper working of which protects from the results of malnutrition[13] by preventing the intake of any excess of food. Thorough mastication and insalivation aid in the more complete utilization of the food and render possible great economy, so that body-weight and nitrogen equilibrium are both maintained on an exceptionally small amount of food. This principle had been worked out by Mr. Horace Fletcher on himself in an attempt to restore his health to a normal condition, with such beneficial results that he was speedily restored to a state of exceptional vigor and well-being. Deliberation in eating, necessitated by the habit of thorough insalivation, it is claimed results in the occurrence of satiety on the ingestion of comparatively small amounts of food, and hence all excess of food is avoided.

In the autumn of 1901, Mr. Fletcher and Dr. van Someren visited the physiological laboratories of Cambridge University, and as stated by Sir Michael Foster[29] the matter was more closely inquired into with the assistance of physiological experts. Observations were carried out on various individuals, and as stated by Professor Foster “the adoption of the habit of thorough insalivation of the food was found in a consensus of opinion to have an immediate and very striking effect upon appetite, making this more discriminating, and leading to the choice of a simple dietary, and in particular reducing the craving for flesh food. The appetite, too, is beyond all question fully satisfied with a dietary considerably less in amount than with ordinary habits is demanded.”... “In two individuals who pushed the method to its limits it was found that complete bodily efficiency was maintained for some weeks upon a dietary which had a total energy value of less than one-half of that usually taken, and comprised little more than one-third of the proteid consumed by the average man.” Finally, says Foster, “it may be doubted if continued efficiency could be maintained with such low values as these, and very prolonged observations would be necessary to establish the facts. But all subjects of the experiments who applied the principles[14] intelligently agreed in finding a very marked reduction in their needs, and experienced an increase in their sense of well-being and an increase in their working powers.”

In the autumn of 1902 and in the early part of 1903, Mr. Fletcher spent several months with the writer, thereby giving an opportunity for studying his habits of life. For a period of thirteen days in January he was under constant observation in the writer’s laboratory, when it was found that the average daily amount of proteid metabolised was 41.25 grams, his body-weight (75 kilos) remaining practically constant. Later, a more thorough series of observations was made, involving a careful analysis of the daily diet, together with analysis of the excreta. For a period of six days the daily diet averaged 44.9 grams of proteid, 38.0 grams of fat, and 253 grams of carbohydrate, the total fuel value amounting to only 1606 large calories per day. The daily intake of nitrogen averaged 7.19 grams, while the daily output through the urine was 6.30 grams and in the fæces 0.6 gram; i. e., a daily intake of 7.19 grams of nitrogen, with a total output of 6.90 grams, showing a daily gain to the body of 0.29 gram of nitrogen, and this on a diet containing less than half the proteid required by the Voit standard and having only half the fuel value of the Voit diet. Further, it was found by careful and thorough tests made at the Yale Gymnasium that Mr. Fletcher, in spite of this comparatively low ration was in prime physical condition. In the words of Dr. Anderson, the Director of the Gymnasium, “the case is unusual, and I am surprised that Mr. Fletcher can do the work of trained athletes and not give marked evidences of over-exertion.... Mr. Fletcher performs this work with greater ease and with fewer noticeable bad results than any man of his age and condition I have ever worked with.”[30] It is not our purpose here to discuss how far these results are due to insalivation, or the more thorough mastication of food. The main point for us is that we have here a striking illustration of the establishment of nitrogen[15] equilibrium on a low proteid diet and great physiological economy as shown by the low fuel value of the food consumed, coupled with remarkable physical strength and endurance.

With data such as these before us we see the possible importance of a fuller and more exact knowledge of true dietary standards. We find here questions suggested, the answers to which are of primary importance in our understanding of the nutritive processes of the body; greater ease in the maintenance of health, increased power of resistance to disease germs, duration of life increased beyond the present average, greater physiological economy and greater efficiency, increased mental and physical vigor with less expenditure of energy on the part of the body. All these questions rise before us in connection with the possibility of maintaining equilibrium on a lowered intake of food, especially nitrogenous equilibrium, with a diminished consumption of proteid or albuminous food. Is it not possible that the accepted dietary standards are altogether too high?

It is of course understood that there can be no fixed dietary standard suitable for all people, ages, and conditions of life. Dietary standards at the best are merely an approximate indication of the amounts of food needed by the body, but these needs are obviously changeable, varying with the degree of activity of the body, especially the amount of physical work performed, to say nothing of differences in body-weight, sex, etc. Further, it is doubtless true that there is what may be called a specific coefficient of nutrition characteristic of the individual, a kind of personal idiosyncrasy which exercises in some degree a modifying influence upon the character and extent of the changes going on in the body. Still, with due recognition of the general influence exerted by these various factors the main question remains, viz., how far the usually accepted standards of diet are correct; or, in other words, is there any real scientific ground for the assumption that the average individual doing an average amount of work requires any such quantity of proteid, or of total nutrients, as the ordinary dietetic standards call for? Cannot all the real physiological[16] needs of the body be met by a greatly reduced proteid intake, with establishment of continued nitrogenous equilibrium on a far smaller amount of proteid food than the ordinary dietary standards call for, and with actual gain to the body?

Just here we may emphasize why prominence is given to the establishment of nitrogenous equilibrium, and why the proteid intake assumes a greater importance than the daily amounts of fat and carbohydrate consumed. Fats and carbohydrates when oxidized in the body are ultimately burned to simple gaseous products, viz., carbonic acid and water. Hence, these waste products are easily and quickly eliminated and cannot exercise much deleterious influence even when formed in excess. To be sure, there is waste of energy in digesting, absorbing, and oxidizing the fats and carbohydrates when they are taken in excessive amounts. Once introduced into the alimentary canal they must be digested, otherwise they will clog the intestine or undergo fermentation, and so cause trouble. Further, when absorbed they may be transformed into fat and deposited in the various tissues and organs of the body; a process desirable up to a certain point, but undesirable when such accumulation renders the body gross and unwieldy. With proteid foods, on the other hand, the story is quite different. These substances, when oxidized, yield a row of crystalline nitrogenous products which ultimately pass out of the body through the kidneys. Prior to their excretion, however, these products—frequently spoken of as toxins—float about through the body and may exercise more or less of a deleterious influence upon the system, or, being temporarily deposited, may exert some specific or local influence that calls for their speedy removal. Hence, the importance of restricting the production of these bodies to the minimal amount, owing to their possible physiological effect and the part they are liable to play in the causation of many diseased conditions. Further, the elimination of excessive amounts of these crystalline nitrogenous bodies through the kidneys places upon these organs an unnecessary burden which[17] is liable to endanger their integrity and possibly result in serious injury, to say nothing of an early impairment of function.

The present experiments were undertaken to throw light upon this broad question of a possible physiological economy in nutrition, and with special reference to the minimal proteid requirement of the healthy man under ordinary conditions of life. The writer as a student of physiology has always maintained that man is disposed to eat far more than the needs of the body require, but his active interest in this problem was aroused especially by his observations of Mr. Fletcher and the marked physiological economy the latter was able to practice, not only without detriment, but apparently with great gain to the body as regards strength, vigor, and endurance, coupled with an apparent resistance to disease. While Mr. Fletcher and Dr. Van Someren would doubtless emphasize the importance of insalivation as a means of controlling the appetite and thereby regulating the consumption of food in harmony with the real needs of the body, it is of primary importance for the physiologist and for mankind to know definitely how far it is possible to reduce the intake of food with perfect safety and without loss of that strength, mental and physical, vigor, and endurance which are characteristic of good health. Further, it is equally plain that if there is possible gain to the body from a practice of physiological economy in diet, we should know how far this can be accomplished by simple restriction in the amount of food without complicating the problem by other factors.

In planning the conduct of this series of experiments the writer has clearly recognized that, while it may be possible, as previous experiments have shown, to maintain body equilibrium and nitrogen equilibrium on a low proteid diet for a brief period, this fact does not, as Munk has previously pointed out, by any means establish the view that such a diet will prove efficient in maintaining equilibrium for a long period, or that bodily strength and vigor can be kept up and the proper resistance to disease secured. Hence, it seemed[18] necessary to so arrange the experiments that they should continue not for a few days or weeks merely, but through months and years. Further, it is very questionable whether the restricted diet (restricted in variety) frequently made use of for convenience in ordinary metabolism experiments is well adapted for bringing out the best results. Hence, it was decided to avoid so far as possible any monotony of diet, giving due recognition to the psychical influences liable to affect secretion, digestion, etc., so admirably worked out by Pawlow in his classical experiments on these subjects; influences which are unquestionably of great importance in controlling and modifying, in some measure at least, the nutritive changes in the body. Again, it is evident that to have experiments of this character broadly useful, they must be tried upon a large number of people and under different conditions of life, in order to avoid so far as possible the influence of personal idiosyncrasy and thereby escape misleading conclusions.

The experiments have been conducted with three distinct types or classes of individuals:

1st. A group of five men of varying ages, connected with the University as professors and instructors; men who while leading active lives have not engaged in very active muscular work. They were selected as representatives of the mental worker rather than the physical worker, although several of them in the performance of their daily duties had to be on their feet in the laboratory a good portion of the day.

2d. A detail of thirteen men, volunteers from the Hospital Corps of the United States Army and representatives of the moderate worker; men who for a period of six months took each week day a vigorous amount of systematic exercise in the gymnasium, in addition to the routine work connected with their daily life as members of the United States Hospital Corps. These men were of different nationalities, ages, and temperaments.

3d. A group of eight young men, students in the University, all thoroughly trained athletes, and some of them with exceptional records in athletic events.


[19]

I. EXPERIMENTS WITH PROFESSIONAL MEN.

Before proceeding with a detailed account of the experimental work, it may be well again to emphasize that what is especially desired is to ascertain how far, if any, the intake of proteid food can be diminished without detriment to the body, i. e., with maintenance of nitrogen and body equilibrium and without impairment of bodily and mental vigor. Further, if a lower proteid standard than that generally adopted can be established, it is desirable to ascertain whether it can be maintained indefinitely, or for a long period of time, without loss of strength and vigor. Obviously, it is of primary importance that we should know quite definitely what the minimal proteid requirement of the healthy man per kilo of body-weight really is, and the experimental work about to be detailed has aimed especially to determine whether it is possible to materially lower the amount of daily proteid food, without detriment to the bodily health and with maintenance of physical and mental vigor.

The writer, fully impressed with his responsibility in the conduct of an experiment of this kind, began with himself in November, 1902. At that time he weighed 65 kilos, was nearly 47 years of age, and accustomed to eating daily an amount of food approximately equal to the so-called dietary standards. Recognizing that the habits of a lifetime should not be too suddenly changed, a gradual reduction was made in the amount of proteid or albuminous food taken each day. In the writer’s case, this resulted in the course of a month or two in the complete abolition of breakfast, except for a small cup of coffee. A light lunch was taken at 1.30 P. M., followed by a heavier dinner at 6.30 P. M. Occasionally, however, the heartier meal was taken at noontime, as the appetite suggested. It should be added that the total intake of food was gradually diminished, as well as the proteid constituents. There was no change, however, to a vegetable diet, but a simple introduction of physiological economy. Still, there was and is now a distinct tendency toward the exclusion of meat in some measure,[20] the appetite not calling for this form of food in the same degree as formerly. At first, this change to a smaller amount of food daily was attended with some discomfort, but this soon passed away, and the writer’s interest in the subject was augmented by the discovery that he was unquestionably in improved physical condition. A rheumatic trouble in the knee joint, which had persisted for a year and a half and which only partially responded to treatment, entirely disappeared (and has never recurred since). Minor troubles, such as “sick headaches” and bilious attacks, no longer appeared periodically as before. There was greater appreciation of such food as was eaten; a keener appetite and a more acute taste seemed to be developed, with a more thorough liking for simple foods. By June, 1903, the body-weight had fallen to 58 kilos.

During the summer the same simple diet was persisted in—a small cup of coffee for breakfast, a fairly substantial dinner at midday and a light supper at night. Two months were spent in Maine at an inland fishing resort, and during a part of this time a guide was dispensed with and the boat rowed by the writer frequently six to ten miles in a forenoon, sometimes against head winds (without breakfast), and with much greater freedom from fatigue and muscular soreness than in previous years on a fuller dietary. The test of endurance and fitness for physical work which the writer thus carried out “on an empty stomach” tended to strengthen the opinion that it is a mistake to assume the necessity for a hearty meal because heavy work is about to be done. It is certainly far more rational from a physiological standpoint to leave the hearty meal until the day’s work is accomplished. We seemingly forget that the energy of muscular contraction comes not from the food-stuffs present at the time in the stomach and intestinal tract, but rather from the absorbed material stored up in the muscles and which was digested and absorbed a day or two before. Further, it is to be remembered that the very process of digestion draws to the gastro-intestinal tract a large supply of blood, and that a large amount of energy is needed for the processes of secretion, digestion, absorption, and[21] peristalsis, which are of necessity incited by the presence of food in the stomach and intestine, thereby actually diminishing the amount of energy available at the place where it is most needed. Why, then, draw upon the resources of the body just at a time, or slightly prior to the time, when the work we desire to perform, either muscular or mental, calls for a copious blood supply in muscle or brain, and when all available energy is needed for the task that is to be accomplished?

We are too wont to compare the working body with a machine, the boiler, engine, etc., overlooking the fact that the animal mechanism differs from the machine in at least one important respect. When we desire to set machinery in operation we must get up steam, and so a fire is started under the boiler and steam is generated in proportion as fuel is burned. The source of the energy made use of in moving the machinery is the extraneous combustible material introduced into the fire-box, but the energy of muscular contraction, for example, comes not from the oxidizable food material in the stomach, but from the material of the muscle itself. In other words, in the animal body it is a part of the tissue framework, or material that is closely incorporated with the framework, that is burned up, and the ability to endure continued muscular strain depends upon the nutritive condition of the muscles involved, and not upon the amount of food contained in, or introduced into, the stomach. All physiologists will, I think, acknowledge the soundness of this reasoning, but how few of us apply the principle in practice. It is perfectly logical to begin the work of the day with a comparatively empty stomach,—after we have once freed ourselves from the habit of a hearty breakfast,—and in the writer’s experience both mental and physical work have become the easier from this change of habit. The muscle and the brain are given opportunity to repair the waste they have undergone, by the taking of food at times when the digestive processes will not draw upon the energy that in activity is needed elsewhere.

Further, it is easy to understand why on a restricted diet, especially of proteid foods, there should be a diminished sense[22] of fatigue in connection with vigorous or continued muscular work, and why at the same time there should be an increased power of endurance, with actual increase of strength. With a diminished intake of proteid food there is a decreased formation of crystalline nitrogenous waste products, such as uric acid and the purin bases, to say nothing of other bodies less fully known, which circulating through the system are undoubtedly responsible, in part at least, for what we term fatigue. We need not consider here whether the sense of fatigue is due to an action of these substances upon the muscles themselves, upon the motor nerves or their end-plates, or upon the central nervous system; it is enough for the present purpose to emphasize the probable results of their presence in undue amount. Lastly, we may emphasize what is pretty clearly evident to-day, viz., that the energy of muscular contraction comes preferably from the oxidation, not of the nitrogenous or proteid constituents of the muscles, but of the non-nitrogenous components of the tissue; another reason why excess of proteid food may be advantageously avoided. Moreover, proteid food stimulates body metabolism in general, and hence undue amounts of proteid in the diet augment unnecessarily the metabolism or combustion of the non-nitrogenous material of the muscle, thereby destroying what would otherwise be preserved as a source of energy in muscular contraction, when the muscles are called upon for the performance of their daily functions.

On the writer’s return to New Haven in the fall of 1903, he was surprised to find that his body-weight was practically the same as early in July. In the period between November, 1902, and July, 1903, the body had lost 8 kilos under the gradual change of diet, but from July to October, 1903, the weight had apparently remained stationary, from which it might fairly be assumed that the body had finally adjusted itself to the new conditions.

What now was the condition of the body as regards nitrogen metabolism? To answer this question the entire twenty-four hours’ urine was collected practically every day, from[23] October 13, 1903, to June 28, 1904, representing a period of nearly nine months. This daily output through the kidneys was analyzed each day with special reference to the total nitrogen,[31] as a measure of the amount of proteid material metabolized. Total volume of the urine, specific gravity, uric acid, phosphoric acid, indican, and other points were also considered, the more important results being indicated in the following tables.

[24]

CHITTENDEN.

Date. Body-weight. Urine.
Volume. 24 hours. Sp. Gr. Nitrogen. Uric Acid. P₂O₅.
1903 kilos c.c. grams gram grams
Oct. 13 57.5 380 1027 5.46 0.376 1.10
14 550 1027 6.51
15 400 1022 5.40 0.352 1.02
16 500 1027 6.45
17 57.4 477 1030 6.40
18 670 1027 7.20 0.406 1.10
19 435 1027 6.13
20 465 1028 6.83 0.476 0.92
21 450 1029 6.51
22 465 1027 6.14 0.370 0.96
27 445 1023 5.52 0.385 0.79
28 405 1027 5.08
Nov. 1 390 1029 5.68 0.372 0.42
2 530 1027 6.33
3 470 1027 5.92 0.412 0.75
4 425 1028 5.88
5 375 1029 4.93 0.330 0.79
7 545 1028 6.57
8 57.4 456 1029 5.82 0.371 0.65
9 415 1027 5.43
10 615 1025 6.45 0.430 1.17
11 410 1028 4.80
12 580 1026 5.64 0.371 1.02
13 584 1027 5.82
14 505 1029 6.36
15 405 1028 5.80 0.384 0.73
16 425 1027 5.43
17 455 1028 5.27 0.367 0.76
18 575 1027 6.62
19 447 1027 5.34 0.389 0.77
20 480 1029 6.00
21 57.5 400 1029 5.71
22 382 1029 5.52 0.379 0.97
23 57.7 350 1029 5.33
24 422 1029 6.43 0.400
25 435 1030 5.79
26 57.6 445 1030 6.09 0.430 1.01
27 430 1030 6.17
29 454 1027 5.66 0.420 0.93
30 455 1023 5.56
[25]Dec. 1 420 1028 5.31 0.450 0.92
2 465 1027 6.17
3 430 1027 5.34 0.350 0.82
4 365 1029 4.77
5 430 1030 5.83
6 515 1028 5.90 0.393 1.08
7 400 1028 5.57
8 390 1028 4.99 0.328 1.02
9 405 1030 5.17
10 57.6 370 1026 4.64 0.308 0.90
11 327 1030 4.65 0.325 1.11
12 390 1027 5.16 0.346 1.01
13 429 1029 5.66
14 360 1030 4.84
15 295 1029 4.32 0.291 0.82
16 445 1029 6.27
17 390 1032 5.59 0.358 0.73
18 420 1030 5.62
19 415 1027 5.03
20 57.5 390 1030 5.71 0.402 0.78
21 360 1023 4.25
22 360 1030 5.13 0.342 0.79
23 400 1031 5.08
24 435 1030 6.44
25 450 1029 5.13 0.329 0.77
26 465 5.55
27 470 5.53
28 535 8.18
29 535 7.67
30 656 9.68
31 57.6 490 1031 7.61 0.455 0.92
1904
Jan. 1 415 1030 6.41
2 490 1031 6.56
3 460 1030 5.91 0.319 0.79
4 58.1 430 1030 5.72
5 570 1028 6.36 0.402
6 445 1028 5.68
7 510 1028 5.91 0.367 0.99
8 420 1028 5.37
[26] 9 650 1027 7.29
10 635 1024 6.32 0.414 0.99
11 410 1028 4.87
12 450 1027 6.48
13 410 1027 5.34 0.435
14 532 1028 6.22 0.502
15 530 1028 5.98
16 515 1030 6.18
17 537 1030 6.73 0.429
18 57.8 395 1029 5.09
19 450 1030 5.72 0.427
20 420 1026 4.76
21 410 1029 5.26 0.401
22 485 1029 5.41
23 440 1031 5.07
24 485 1029 5.61 0.407
25 545 1027 6.18
26 485 1028 6.69 0.440
27 435 1028 5.64
28 490 1029 6.18 0.423
29 450 1029 5.68
30 475 5.59 0.376
31 490 6.61
Feb. 1 490 1030 6.47
2 57.5 400 1031 6.12 0.219
3 415 1030 5.85
4 545 1027 6.77 0.327
5 450 1030 5.64
6 485 1027 6.01
7 450 1026 5.62
8 57.4 415 1027 5.88
9 540 1026 6.67 0.449
10 410 1029 5.61
11 600 1025 6.70
12 430 1029 5.57 0.437
13 415 1028 5.50
14 480 1028 6.42 0.497
15 395 1030 4.95
16 500 1029 5.97 0.364
17 450 1030 5.62
[27] 18 57.3 430 1030 5.86 0.279
19 450 1029 6.21
20 455 1027 5.46
21 500 1027 6.16 0.424
22 445 1028 5.15
23 455 1027 5.63
24 420 1028 6.27
25 560 1027 6.28 0.403
26 630 1026 6.27
27 570 1026 6.87
28 515 1028 6.27 0.496
29 450 1030 5.43
Mar. 1 450 1027 6.02
2 445 1029 5.15
3 590 1028 6.30
4 415 1029 5.40
5 57.5 425 1027 5.48
6 548 1025 5.92 0.370
7 400 1029 4.68
8 530 1028 5.77
9 560 1028 5.84
10 560 1028 5.64
11 495 1028 5.79
12 515 1021 6.80
13 520 1029 6.43 0.370
14 600 1025 6.12
15 520 1026 5.87
16 57.5 525 1026 5.13
17 490 1026 4.97
18 450 1027 5.08
19 500 1024 5.85
20 500 1022 5.91 0.321
daily
average
1.20
daily
average
21 57.4 430 1025 5.52
22 458 1033 5.94
23 57.2 400 1029 5.61
24 57.3 365 1029 4.31
25 420 1029 5.39
26 57.5 435 1027 5.85
27 595 1026 6.33
28 545 1027 6.00
[28] 29 435 1028 4.86
30 575 1026 6.26
31 495 1026 5.26
Apr. 1 570 1026 6.33
2 440 1030 6.07
3 487 1026 6.11 0.375
4 410 1028 5.78
5 390 1028 5.38
6 56.8 490 1028 5.56
7 56.5 530 1027 5.69
8 440 1029 5.41
9 465 1019 6.05
10 56.8 500 1029 6.00 0.382
11 500 1028 6.18
12 56.4 475 1029 5.55 0.366 0.870
Daily average
for six months
466 1027 5.82 0.386 0.899
13 545 1029 6.77
14 440 1027 5.89
15 500 1028 5.91
16 485 1028 5.49
17 405 1029 5.99 0.393
18 465 1029 6.11
19 510 1030 7.68
20 430 1031 6.99
21 56.6 615 1029 8.67
22 320 1030 5.03
23 57.1 355 1032 5.72
24 455 1027 5.97
25 380 1027 4.93
26 450 1028 4.97 0.366
27 600 1025 6.62 0.553
28 56.9 385 1029 5.66 0.507
29 415 1029 5.28 0.488
30 56.9 462 1029 5.59 0.413
May 1 486 1027 5.54 0.409
2 405 1028 4.11 0.320
3 57.1 505 1027 5.48
4 456 1026 5.27
5 380 1026 4.88
[29] 6 530 1027 6.30
7 470 1024 5.44
8 57.6 460 1027 5.07
9 460 1026 4.28
10 57.4 493 1028 5.26
11 415 1029 4.61
12 530 1029 5.98
13 415 1031 4.72
14 57.2 405 1031 4.98 0.468
15 500 1029 5.31
16 505 1027 5.03
17 650 1020 5.69
18 550 1027 5.81
19 560 1027 6.05
20 615 1027 6.64
21 56.9 380 1032 5.20 0.421
22 475 1028 5.73
23 378 1028 4.60
24 383 1029 4.48
25 535 1025 5.14
26 56.9 355 1028 4.37
27 435 1026 4.93
28 57.5 555 1028 5.99 0.397
29 57.7 565 1027 6.27
30 700 1020 5.50
31 500 1025 5.13
June 1 630 1023 5.41
2 510 1020 4.16
3 530 1023 5.25
4 57.6 390 1029 5.25
5 400 1025 4.87
6 430 1027 5.16
7 480 1028 5.15
8 410 1027 4.95
9 420 1026 4.51
10 395 1026 4.27
11 57.5 510 1030 5.91
12 530 1027 5.95
13 57.6 485 1027 5.35
14 470 1030 5.16
[30] 15 560 1024 4.91
16 57.6 390 1029 5.26
17 408 1027 5.17
18 57.9 412 1030 5.07
19 458 1025 5.44
20 58.0 380 1026 4.49
21 480 1023 5.04
22 57.8 580 1025 6.16
23 57.9 535 1025 5.26 0.397
daily
average
1.08
daily
average
24 57.6 570 1024 5.30
25 410 1027 4.43
26 57.4 400 1027 4.66
27 57.4 405 1027 4.98
Daily average from Oct. 13, 1903 468 1027 5.69 0.392 0.904
Daily average from April 13 to June 27 5.40
June 28 57.5 595 1026 6.75

Scrutiny of the tables shows that during this period of nine months the body-weight was practically constant. The daily volume of urine was exceptionally small and fairly regular in amount, the average daily output for the nine months being 468 c.c. It is a noticeable fact that with a diminished intake of proteid food there is far less thirst, and consequently a greatly decreased demand for water or other fluids. Further, in view of the small nitrogenous waste there is no need on the part of the body for any large amount of fluid to flush out the kidneys. The writer has not had a turbid urine during the nine months’ period. With heavier eating of nitrogenous foods, an abundant water supply is a necessity to prevent the kidneys from becoming clogged, thereby explaining the frequent beneficial results of the copious libations of mineral[31] waters, spring waters, etc., frequently called for after, or with, heavy eating. Obviously, a small volume of urine each day means so much less wear and tear of the delicate mechanism of the kidneys. Somewhat noticeable, in a general way, is the apparent relationship between the volume of the urine and the nitrogen output, in harmony with the well-known diuretic action of urea. The specific gravity of the urine shows variation only within narrow limits, the daily average for the nine months being 1027.

Uric acid is noticeably small in quantity, the average daily output for the nine months’ period, based upon the determinations made, being only 0.392 gram.

Chief interest, however, centres around the figures for total nitrogen, since these figures give for each day the extent of the proteid metabolism; i. e., the amount of proteid material broken down in the body each day in connection with the wear and tear of the bodily machinery. To fully grasp the significance of these data, it should be remembered that the prevalent dietary standards are based upon the assumption that the average adult must metabolize each day at least 16 grams of nitrogen. Indeed, that is what actual analysis of the urine indicates in most cases. If now we look carefully through the figures shown in the above tables, covering a period from October 13, 1903, to June 28, 1904, it is seen that the daily nitrogen excretion is far different from 16 grams. Indeed, the figures for nitrogen are exceedingly low, and, moreover, they vary little from day to day. The average daily output of nitrogen through the urine for the entire period of nearly nine months is only 5.699 grams.

For the first six months the average daily excretion amounted to 5.82 grams of nitrogen, while from April 12 to June 28 the average daily excretion of nitrogen was 5.40 grams, thus showing a slight tendency downward. On the whole, however, there is shown a somewhat remarkable uniformity in the daily excretion. Thus, the average daily excretion for the month of November was 5.79 grams of nitrogen, for the month of March 5.66 grams, thus showing very little[32] difference in the output of nitrogen through the kidneys in these two periods, three months apart. In other words, the extent of proteid katabolism was essentially the same throughout the entire nine months, implying that the amount of proteid food eaten must have been fairly constant, and that the body had adapted itself to this new level of nutrition from which there was no tendency to deviate. There was no weighing out of food and no attempt to follow any specified diet. The greatest possible variety of simple foods was indulged in, and the dictates of the appetite were followed with the single precaution that excess was avoided. In other words, it was temperance in diet, and not prohibition. Yet it is equally true, in the writer’s case at least, that the appetite itself unconsciously served as a regulator, since there was, as a rule, no necessity to hold the appetite in check to avoid excess. Doubtless, the writer’s knowledge of the general composition of food-stuffs has had some influence in the choice of foods, and thereby aided in bringing about this somewhat remarkable uniformity in the daily output of nitrogen for such a long period of time on an unrestricted diet.

What now do the nitrogen figures show regarding the amount of proteid material metabolized each day? It will be remembered that the Voit standard calls for 118 grams of proteid or albuminous food daily, of which 105 grams should be absorbable, in order to maintain the body in a condition of nitrogen equilibrium, and in a state of physical vigor and general tone. This would mean a daily excretion through the urine of at least 16 grams of nitrogen. The daily output of nitrogen in the case under discussion, however, was 5.699 grams for a period of nearly nine months. This amount of nitrogen excreted through the urine means only 35.6 grams of proteid metabolized, or about one-third the amount called for by the Voit standard, or the standards generally adopted as expressing man’s daily requirement of proteid food. But was the body in nitrogenous equilibrium on this small amount of proteid food? Naturally, this question might be answered in the affirmative, on the basis of the constancy in body-weight[33] for the period from October to June, but more decisive proof is needed. The question was therefore settled by a careful comparison of the income and output, in which all the food eaten was carefully weighed and analyzed, while the nitrogen of the urine and fæces was determined with equal accuracy. The first experiment of this character to be quoted is for the week commencing March 20, a period of six days.

Following are the diets made use of each day, the weights of the various food-stuffs being given in grams. Likewise is shown the nitrogen content of the several food-stuffs for each day, and also a comparison of the nitrogen intake with the output of nitrogen through the urine:

[34]

Sunday, March 20, 1904.

Breakfast, 7.45 A. M.—One cup coffee, i. e., coffee 137.5 grams, cream 30.5 grams, sugar 9 grams.

Dinner, 1.30 P. M.—Stewed chicken 50 grams, mashed potato 131 grams, biscuit 49 grams, butter 13 grams, chocolate pudding 106 grams, one small cup coffee, i. e., coffee 64 grams, sugar 12 grams, cheese crackers 29 grams.

Supper, 6.30 P. M.—Lettuce sandwiches 56 grams, biscuit 35 grams, butter 6 grams, one cup tea, i. e., tea 170 grams, sugar 7 grams, sponge cake 47 grams, sliced oranges 82 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Coffee 64 + 137 = 201.5 × 0.042 = 0.085 gram.
Cream 30.5 × 0.41 = 0.125
Sugar 12 + 9 + 7 = 28.0 × 0.00 = 0.000
Chicken 50.0 × 4.70 = 2.350
Mashed potato 131.0 × 0.30 = 0.393
Biscuit 35 + 49 = 84.0 × 1.49 = 1.251
Butter 13 + 6 = 19.0 × 0.10 = 0.019
Chocolate pudding 106.0 × 0.86 = 0.911
Cheese crackers 29.0 × 2.54 = 0.737
Lettuce sandwich 56.0 × 0.92 = 0.515
Tea 170.0 × 0.048 = 0.082
Sponge cake 47.0 × 0.98 = 0.461
Sliced orange 82.0 × 0.073 = 0.060
Total nitrogen in food 6.989 grams.
Total nitrogen in urine 5.910
Fuel value of the food 1708 calories.[32]

[35]

Monday, March 21, 1904.

Breakfast, 7.45 A. M.—Coffee 119 grams, cream 30 grams, sugar 9 grams.

Lunch, 1.30 P. M.—One shredded wheat biscuit 31 grams, cream 116 grams, wheat gems 33 grams, butter 7 grams, tea 185 grams, sugar 10 grams, cream cake 53 grams.

Dinner, 6.30 P. M.—Pea soup 114 grams, lamb chop 24 grams, boiled sweet potato 47 grams, wheat gems 76 grams, butter 13 grams, cream cake 52 grams, coffee 61 grams, sugar 10 grams, cheese crackers 16 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Coffee 119 + 61 = 180 × 0.042 = 0.076 gram.
Cream 30 + 116 = 146 × 0.41 = 0.600
Sugar 9 + 10 + 10 = 29 × 0.00 = 0.000
Shredded wheat biscuit 31 × 1.62 = 0.502
Tea 185 × 0.048 = 0.089
Wheat gems 33 + 76 = 109 × 1.46 = 1.591
Butter 7 + 13 = 20 × 0.10 = 0.020
Cream cake 53 + 52 = 105 × 0.97 = 1.018
Pea soup 114 × 1.00 = 1.140
Lamb chop 24 × 4.54 = 1.090
Sweet potato 47 × 0.18 = 0.085
Cheese crackers 16 × 2.54 = 0.410
Total nitrogen in food 6.621 grams.
Total nitrogen in urine 5.520
Fuel value of the food 1713 calories.

[36]

Tuesday, March 22, 1904.

Breakfast, 7.45 A. M.—Coffee 97 grams, cream 26 grams, sugar 9 grams.

Lunch, 1.30 P. M.—Baked potato 83 grams, fried sausage 36 grams, soda biscuit 39 grams, butter 12 grams, tea 137 grams, sugar 10 grams, cream meringue 59 grams.

Dinner, 6.30 P. M.—Chicken broth 146 grams, bread 52 grams, butter 15 grams, creamed potato 76 grams, custard 76 grams, coffee 50 grams, sugar 11 grams, cheese crackers 10 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Coffee 97 + 50 = 147 × 0.042 = 0.060 gram.
Cream 26 × 0.42 = 0.109
Sugar 9 + 10 + 11 = 30 × 0.00 = 0.000
Baked potato 83 × 0.40 = 0.332
Fried sausage 36 × 3.06 = 1.101
Soda biscuit 39 × 1.66 = 0.647
Butter 12 + 15 = 27 × 0.10 = 0.027
Tea 137 × 0.048 = 0.066
Cream meringue 59 × 0.92 = 0.543
Chicken broth 146 × 0.78 = 1.138
Bread 52 × 1.66 = 0.863
Creamed potato 76 × 0.42 = 0.319
Custard 76 × 0.82 = 0.623
Cheese crackers 10 × 2.54 = 0.254
Total nitrogen in food 6.082 grams.
Total nitrogen in urine 5.940
Fuel value of the food 1398 calories.

[37]

Wednesday, March 23, 1904.

Breakfast, 7.45 A. M.—Coffee 103 grams, cream 30 grams, sugar 10 grams.

Lunch, 1.30 P. M.—Creamed codfish 64 grams, potato balls 54 grams, biscuit 44 grams, butter 22 grams, tea 120 grams, sugar 10 grams, wheat griddle cakes 133 grams, maple syrup 108 grams.

Dinner, 6.30 P. M.—Creamed potato 85 grams, biscuit 53 grams, butter 15 grams, apple-celery-lettuce salad 50 grams, apple pie 127 grams, coffee 67 grams, sugar 8 grams, cheese crackers 17 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Coffee 103 + 67 = 170 × 0.042 = 0.071 gram.
Sugar 10 + 10 + 8 = 28 × 0.00 = 0.000
Cream 30 × 0.43 = 0.129
Potato balls 54 × 0.68 = 0.367
Creamed codfish 64 × 1.26 = 0.806
Biscuit 44 + 53 = 97 × 1.66 = 1.610
Butter 22 + 15 = 37 × 0.10 = 0.037
Tea 120 × 0.048 = 0.058
Wheat griddle cakes 133 × 1.32 = 1.760
Maple syrup 108 × 0.019 = 0.021
Creamed potato 85 × 0.53 = 0.450
Cheese crackers 17 × 2.54 = 0.431
Apple-celery salad 50 × 0.20 = 0.100
Apple pie 127 × 0.75 = 0.953
Total nitrogen in food 6.793 grams.
Total nitrogen in urine 5.610
Fuel value of the food 1984 calories.

[38]

Thursday, March 24, 1904.

Breakfast, 7.45 A. M.—Coffee 100 grams, cream 25 grams, sugar 8 grams.

Lunch, 1.30 P. M.—Shredded wheat biscuit 29 grams, cream 118 grams, wheat gems 60 grams, butter 8 grams, tea 100 grams, sugar 7 grams, apple pie 102 grams.

Dinner, 6.30 P. M.—Milk-celery soup 140 grams, bread 15 grams, butter 1 gram, lettuce sandwiches 62 grams, tea 100 grams, sugar 10 grams, lemon pie 109 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Coffee 100 × 0.042 = 0.042 gram.
Cream 25 + 118 = 143 × 0.43 = 0.615
Sugar 8 + 7 + 10 = 25 × 0.00 = 0.000
Shredded wheat biscuit 29 × 1.76 = 0.510
Wheat gems 60 × 1.17 = 0.702
Butter 8 + 1 = 9 × 0.10 = 0.009
Tea 100 + 100 = 200 × 0.048 = 0.096
Apple pie 102 × 0.75 = 0.765
Milk-celery soup 140 × 0.42 = 0.588
Bread 15 × 1.36 = 0.204
Lettuce sandwich 62 × 1.02 = 0.632
Lemon pie 109 × 0.82 = 0.894
Total nitrogen in food 5.057 grams.
Total nitrogen in urine 4.310
Fuel value of the food 1594 calories.

[39]

Friday, March 25, 1904.

Breakfast, 7.45 A. M.—Coffee 100 grams, cream 25 grams, sugar 9 grams.

Lunch, 1.30 P. M.—Halibut with egg sauce 108 grams, mashed potato 89 grams, biscuit 48 grams, butter 10 grams, chocolate-cream cake 90 grams, tea 100 grams, sugar 9 grams.

Dinner, 6.30 P. M.—Milk-celery soup 121 grams, lettuce sandwiches 61 grams, creamed potato 65 grams, lettuce-apple-celery salad 74 grams, coffee 70 grams, sugar 10 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Coffee 100 + 70 = 170 × 0.042 = 0.071 gram.
Cream 25 × 0.40 = 0.100
Sugar 9 + 9 + 10 = 28 × 0.00 = 0.000
Halibut, etc. 108 × 3.02 = 3.262
Mashed potato 89 × 0.26 = 0.231
Biscuit 48 × 1.52 = 0.730
Butter 10 × 0.10 = 0.010
Tea 100 × 0.048 = 0.048
Chocolate-cream cake 90 × 0.99 = 0.891
Celery-milk soup 121 × 0.52 = 0.629
Lettuce sandwich 61 × 0.98 = 0.598
Lettuce-apple salad 74 × 0.21 = 0.155
Creamed potato 65 × 0.37 = 0.241
Total nitrogen in food 6.966 grams.
Total nitrogen in urine 5.390
Fuel value of the food 1285 calories.

[40]

NITROGEN BALANCE.—Chittenden.

Nitrogen
Taken in.
Output.
Nitrogen in Urine. Weight of Fæces[33] (dry).
March 20 6.989 grams. 5.91 grams. 3.6 grams.
21 6.621 5.52 0.0
22 6.082 5.94 12.0
23 6.793 5.61 18.5
24 5.057 4.31 23.0
25 6.966 5.39 16.9
74.0 grams contain
6.42% N.
38.508 32.68 + 4.75 grams nitrogen.
38.508 grams nitrogen. 37.43 grams nitrogen.
Nitrogen balance for six days = +1.078 grams.
Nitrogen balance per day = +0.179 gram.

Average Intake.

Calories per day 1613.
Nitrogen per day 6.40 grams.

[41]

Examination of the results shown in the foregoing balance makes it quite clear that the body was essentially in nitrogenous equilibrium. Indeed, there was a slight plus balance, showing that even with the small intake of proteid food the body was storing up nitrogen at the rate of 0.16 gram per day. The average daily intake of nitrogen for the six days’ period was 6.40 grams, equal to 40.0 grams of proteid or albuminous food. The average daily output of nitrogen through the urine and fæces was 6.24 grams. The average daily output of nitrogen through the urine for the six days’ period was 5.44 grams, corresponding to the metabolism of 34 grams of proteid material. When these figures are contrasted with the usually accepted standards of proteid requirement for the healthy man, they are certainly somewhat impressive, especially when it is remembered that the body at that date had been in essentially this same condition for at least six months, and probably for an entire year. The Voit standard of 118 grams of proteid, with an equivalent of at least 18 grams of nitrogen and calling for the metabolism of 105 grams of proteid, or 16.5 grams of nitrogen per day, makes clear how great a physiological economy had been accomplished. In other words, the consumption of proteid food was reduced to at least one-third the daily amount generally considered as representing the average requirement of the healthy man, and this with maintenance of body-weight at practically a constant point for the preceding ten months, and, so far as the writer can observe, with no loss of vigor, capacity for mental and physical work, or endurance. Indeed, the writer is disposed to maintain that he has done more work and led a more active life in every way during the period of this experiment, and with greater comfort and less fatigue than usual. His health has certainly been of the best during this period.

In this connection it may be well to call attention to the completeness of the utilization of the daily food in this six days’ experiment, as shown by the small amount of refuse discharged per rectum, indicating as it does the high efficiency of the digestive processes and of the processes of absorption.[42] The refuse matter for the entire period of six days amounted when dry to only 74 grams, and when it is remembered how large a proportion of this refuse must of necessity be composed of the cast-off secretions from the body, it will be seen how thorough must have been the utilization of the food by the system. The loss of nitrogen to the body per day through the fæces amounted to only 0.79 gram, and this on a mixed diet containing considerable matter not especially concentrated, and on some days with noticeable amounts of food, such as salads, not particularly digestible.

Finally, emphasis should be laid upon the fact that this economy of proteid food, this establishment of nitrogen equilibrium on a low proteid intake, was accomplished without increase in the daily intake of non-nitrogenous foods. In fact, the amount of fats and carbohydrates was likewise greatly reduced, far below the minimal standard of 3000 calories as representing the potential energy or fuel value of the daily diet. Indeed, during the balance period of six days just described the average fuel value of the food per day was only a little over 1600 calories.

As the experiment continued and the record for the months of April and May was obtained, it became evident from the nitrogen results that the rate of proteid katabolism was being still more reduced. A second balance experiment was therefore tried with a view to seeing if the body was still in nitrogen equilibrium, and also to ascertain whether the fuel value of the food still showed the same low calorific power. For a period of five days, June 23 to 27, the intake of food and the entire output were carefully compared, with the results shown in the accompanying tables.

[43]

Thursday, June 23, 1904.

Breakfast.—Coffee 123 grams, cream 50 grams, sugar 11 grams.

Lunch.—Omelette 50 grams, French fried potatoes 70 grams, bacon 10 grams, wheat gems 43 grams, butter 9 grams, strawberries 125 grams, sugar 20 grams, cream cake 59 grams.

Dinner.—Beefsteak 34 grams, peas 60 grams, creamed potato 97 grams, bread 26 grams, butter 17 grams, lettuce-orange salad 153 grams, crackers 43 grams, cream cheese 15 grams, coffee 53 grams, sugar 12 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Coffee 123 + 53 = 176 × 0.045 = 0.079 gram.
Cream 50 × 0.35 = 0.175
Sugar 11 + 20 + 12 = 43 × 0.00 = 0.000
Omelette 50 × 1.32 = 0.660
French fried potatoes 70 × 0.37 = 0.259
Bacon 10 × 3.43 = 0.343
Wheat gems 43 × 1.49 = 0.641
Butter 9 + 17 = 26 × 0.13 = 0.034
Strawberries 125 × 0.11 = 0.138
Cream cake 59 × 0.98 = 0.578
Beefsteak 34 × 4.14 = 1.408
Peas 60 × 0.97 = 0.582
Creamed potato 97 × 0.34 = 0.330
Bread 26 × 1.23 = 0.320
Lettuce-orange salad 153 × 0.15 = 0.230
Crackers 43 × 1.40 = 0.602
Cream cheese 15 × 1.62 = 0.243
Total nitrogen in food 6.622 grams.
Total nitrogen in urine 5.260
Fuel value of the food 1863 calories.

[44]

Friday, June 24, 1904.

Breakfast.—Coffee 96 grams, sugar 8 grams, milk 32 grams.

Lunch.—Creamed codfish 89 grams, baked potato 95 grams, butter 10 grams, hominy gems 58 grams, strawberries 86 grams, sugar 26 grams, ginger snaps 47 grams.

Dinner.—Cold tongue 14 grams, fried potato 48 grams, peas 60 grams, wheat gems 30 grams, butter 11 grams, lettuce-orange salad with mayonnaise dressing 155 grams, crackers 22 grams, cream cheese 14 grams, ginger snaps 22 grams, coffee 58 grams, sugar 10 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Coffee 123 + 53 = 176 × 0.045 = 0.079 gram.
Sugar 8 + 26 + 10 = 44 × 0.00 = 0.000
Milk 32 × 0.51 = 0.163
Creamed codfish 89 × 1.78 = 1.584
Baked potato 95 × 0.29 = 0.276
Butter 10 + 11 = 21 × 0.13 = 0.027
Hominy gems 58 × 1.20 = 0.696
Strawberries 86 × 0.11 = 0.095
Ginger snaps 47 + 22 = 69 × 1.15 = 0.794
Cold tongue 14 × 4.87 = 0.682
Fried potato 48 × 0.37 = 0.178
Peas 60 × 0.94 = 0.564
Wheat gems 30 × 1.45 = 0.435
Lettuce-orange salad, etc. 155 × 0.15 = 0.233
Crackers 22 × 1.40 = 0.308
Cream cheese 14 × 1.62 = 0.227
Total nitrogen in food 6.331 grams.
Total nitrogen in urine 5.300
Fuel value of the food 1506 calories.

[45]

Saturday, June 25, 1904.

Breakfast.—Coffee 101 grams, milk 36 grams, sugar 13 grams.

Lunch.—Omelette 50 grams, bacon 9 grams, French fried potato 23 grams, biscuit 29 grams, butter 8 grams, cream cheese 17 grams, iced tea 150 grams, sugar 15 grams, ginger snaps 42 grams.

Dinner.—Wheat popovers 57 grams, butter 10 grams, lettuce-orange salad with mayonnaise dressing 147 grams, cream cheese 21 grams, crackers 22 grams, cottage pudding 82 grams, coffee 48 grams, sugar 11 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Coffee 1201 + 48 = 149 × 0.045 = 0.067 gram.
Milk 36 × 0.46 = 0.166
Sugar 13 + 15 + 11 = 39 × 0.00 = 0.000
Omelette 50 × 1.42 = 0.710
Bacon 9 × 2.66 = 0.239
French fried potato 23 × 0.57 = 0.131
Biscuit 29 × 1.35 = 0.392
Butter 8 + 10 = 18 × 0.13 = 0.023
Iced tea 150 × 0.018 = 0.027
Ginger snaps 42 × 1.15 = 0.483
Cream cheese 17 + 21 = 38 × 1.62 = 0.616
Wheat popovers 57 × 1.64 = 0.935
Lettuce-orange salad 147 × 0.15 = 0.221
Crackers 22 × 1.40 = 0.308
Cottage pudding 82 × 0.76 = 0.623
Total nitrogen in food 4.941 grams.
Total nitrogen in urine 4.430
Fuel value of the food 1392 calories.

[46]

Sunday, June 26, 1904.

Breakfast.—Coffee 122 grams, cream 31 grams, sugar 8 grams.

Dinner.—Roast lamb 50 grams, baked potato 52 grams, peas 64 grams, biscuit 32 grams, butter 12 grams, lettuce salad 43 grams, cream cheese 21 grams, toasted crackers 23 grams, blanc mange 164 grams.

Supper.—Iced tea 225 grams, sugar 29 grams, lettuce sandwich 51 grams, strawberries 130 grams, sugar 22 grams, cream 40 grams, sponge cake 31 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Coffee 122 × 0.045 = 0.055 gram.
Cream 31 + 40 = 71 × 0.32 = 0.227
Sugar 8 + 26 + 10 = 44 × 0.00 = 0.000
Roast lamb 50 × 4.28 = 2.140
Baked potato 52 × 0.29 = 0.151
Peas 64 × 1.04 = 0.666
Biscuit 32 × 1.35 = 0.432
Butter 12 × 0.13 = 0.016
Lettuce salad 43 × 0.23 = 0.099
Cream cheese 21 × 1.62 = 0.340
Toasted crackers 23 × 1.36 = 0.313
Blanc mange 164 × 0.35 = 0.574
Iced tea 225 × 0.018 = 0.041
Lettuce sandwich 51 × 0.85 = 0.434
Strawberries 130 × 0.11 = 0.143
Sponge cake 31 × 0.94 = 0.291
Total nitrogen in food 5.922 grams.
Total nitrogen in urine 4.660
Fuel value of the food 1533 calories.

[47]

Monday, June 27, 1904.

Breakfast.—Coffee 112 grams, cream 22 grams, sugar 10 grams.

Lunch.—Roast lamb 9 grams, baked potato 90 grams, wheat gems 47 grams, butter 12 grams, sugar 25 grams, iced tea 250 grams, vanilla éclair 47 grams.

Dinner.—Lamb chop 32 grams, asparagus 49 grams, butter 17 grams, creamed potato 107 grams, bread 35 grams, lettuce-orange salad with mayonnaise dressing 150 grams, cream cheese 12 grams, crackers 21 grams, coffee 63 grams, sugar 9 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Coffee 123 + 53 = 176 × 0.045 = 0.079 gram.
Cream 22 × 0.32 = 0.070
Sugar 10 + 25 + 9 = 44 × 0.00 = 0.000
Iced tea 250 × 0.018 = 0.045
Baked potato 90 × 0.25 = 0.225
Wheat gems 47 × 1.65 = 0.776
Butter 12 + 17 = 29 × 0.13 = 0.038
Roast lamb 9 × 4.28 = 0.385
Vanilla éclair 47 × 0.85 = 0.400
Lamb chops 32 × 4.57 = 1.462
Asparagus 49 × 0.59 = 0.289
Creamed potato 107 × 0.40 = 0.428
Bread 35 × 1.33 = 0.466
Lettuce-orange salad, etc. 150 × 0.23 = 0.345
Cream cheese 12 × 1.62 = 0.194
Crackers 21 × 1.35 = 0.284
Total nitrogen in food 5.486 grams.
Total nitrogen in urine 4.980
Fuel value of the food 1454 calories.

[48]

NITROGEN BALANCE.—Chittenden.

Nitrogen
Taken in.
Output.
Nitrogen in Urine. Weight of Fæces (dry).
June 23 6.622 grams. 5.26 grams. 10.6 grams.
24 6.331 5.30 0.7
25 4.941 4.43 14.2
26 5.922 4.66 11.9
27 5.486 4.98 15.2
82.6 grams contain
6.08% N.
29.302 24.63 + 5.022 grams nitrogen.
29.302 grams nitrogen. 29.652 grams nitrogen.
Nitrogen balance for five days = -0.350 gram.
Nitrogen balance per day = -0.070 gram.

Average Intake.

Calories per day 1549.
Nitrogen per day 5.860 grams.

[49]

Examination of these figures makes quite clear that the body was still in nitrogen equilibrium, or essentially so, the minus balance being so small as to have little significance. The body-weight was still stationary, and yet during this balance period the average daily intake of nitrogen was only 5.86 grams, corresponding to 36.62 grams of proteid or albuminous food. Further, the average daily fuel value of the food was only 1549 calories, a trifle less than in the preceding period. The average daily output of nitrogen through the urine for this period was 4.92 grams, corresponding to the metabolism of 30.7 grams of proteid food. Hence, the results of this period confirm those of the preceding period and make it quite clear that this subject, with a body-weight of 57.5 kilos, can be maintained in body equilibrium, and in nitrogen equilibrium, on a daily diet containing only 5.8 grams of nitrogen and with a fuel value of about 1600 calories. Under these conditions, as in the last balance period, the daily amount of nitrogen metabolized was very small, averaging only 4.92 grams. Comparison of this figure with the accepted standard of 16 grams of nitrogen makes quite clear the extent of the physiological economy which is attainable by the body, and emphasizes also the extent of the unnecessary and worse than useless labor put upon the body by the prevalent dietetic habits of the majority of mankind.

It is of course understood that the low fuel value which sufficed to keep the writer in body equilibrium would not meet the requirements of a more active life, with greater physical labor. The writer has led a very busy life during the year of this experiment, but it has been mental activity rather than physical, although doubtless he has exercised as much as the ordinary professional worker not accustomed to athletic sports. The results of the experiment, however, make it quite clear that a man of the above body-weight, even though he lead a very active life—not involving great physical labor—can maintain his body in equilibrium indefinitely with an intake of 36 to 40 grams of proteid or albuminous food, and with a total fuel value of about 1600 calories. Further, it is to be[50] understood that there is no special form of diet involved in the accomplishment of such a result. Scrutiny of the daily diet, tabulated in the two balance periods, will show the character of the food made use of. Personal likes and dislikes must naturally enter into the choice of any diet, and freedom of choice, freedom to follow the dictates of one’s appetite, with such regulation as comes from the use of reason and intelligence, are all that is necessary to secure the desired end. Physiological economy in nutrition is easily attainable and does not involve the adoption of vegetarianism. It does mean, however, temperance and simplicity in diet, coupled with intelligent regulation, which, however, soon becomes a habit and eventually leads to a moderation in diet which fully satisfies all the cravings of appetite as completely as it suffices to maintain the body in equilibrium and in a general condition of health and vigor.

Taking the data recorded above, we may now calculate the nitrogen requirement of the body per kilo of body-weight. With the body-weight placed at 57 kilos and with an average daily elimination of nitrogen for nearly nine months of 5.699 grams, or practically 5.7 grams, it is evident that the nitrogen metabolized per kilo of body-weight in the present instance was exactly 0.1 gram. If we take the lower figure of 5.40 grams of nitrogen, the average daily excretion from April 13 to June 27, we find the nitrogen requirement to be 0.0947 gram per kilo of body-weight. Translating these figures into terms of proteid or albuminous matter, they mean the utilization or metabolism of 0.625 gram of proteid matter daily per kilo of body-weight, under the conditions of life, activity, and general food consumption prevailing throughout this period of nearly nine months with this particular individual.

Whether we are justified in saying that this figure represents the minimal proteid requirement of this particular individual is perhaps questionable, since the proteid or nitrogen requirement will of necessity vary somewhat with the amount of non-nitrogenous food consumed. Doubtless, the nitrogen metabolism could be reduced still lower by increasing[51] the intake of non-nitrogenous food, but under the above conditions of life, following a plan of living both congenial and satisfactory, one that fully sufficed to keep the body in equilibrium and with the practice of a general physiological economy, we may say that the metabolism of 0.1 gram of nitrogen per kilo of body-weight was quite sufficient to meet all the requirements of the body. Health, strength, mental and physical vigor have been maintained unimpaired, and there is a growing conviction that in many ways there is a distinct improvement in both the physical and mental condition. Greater freedom from fatigue, greater aptitude for work, greater freedom from minor ailments, have gradually become associated in the writer’s mind with this lowered proteid metabolism and general condition of physiological economy. The writer, however, is fully alive to the necessity of caution in the acceptance of one’s feelings as a measure of physical or mental condition, but he has been keenly watchful for any and every sign or symptom during the course of these experiments, and is now strongly of the opinion that there is much good to be gained in the adoption of dietetic habits that accord more closely with the true physiological needs of the body. If a man of 57 kilos body-weight can maintain a condition of equilibrium, with continuance of health, strength, and vigor (to say nothing of possible improvement), with a daily consumption of say 40 grams of proteid food and sufficient non-nitrogenous food to yield 2000 calories, why should he load up his system each day with three times this amount of proteid food, with enough more fat and carbohydrate to yield 3000 plus calories?

Finally, the writer in summing up his own experience is inclined to say that while he entered upon this experiment simply with a view to studying the question from a purely scientific and physiological standpoint, he has become so deeply impressed with the great gain to the body by this practice of physiological economy, and his system has become so accustomed to the new level of nutrition that there is no desire to return to the more liberal dietetic habits of former years.

[52]

Obviously, it is not wise nor safe to draw too broad deductions from a single individual, nor from a single experiment even though it extends over a long period of time; consequently, we may turn our attention to other individuals with presumably different personality and different habits of life. The writer’s colleague, Dr. Lafayette B. Mendel, Professor of Physiological Chemistry in the Sheffield Scientific School, kindly volunteered to become a subject of experiment. With a body-weight of 76 kilos, 32 years of age, and of strong physique, he commenced to modify his diet about the middle of October, 1903, diminishing gradually the amount of proteid food with the results shown in the following tables, where are given, as in the preceding experiment, the amounts of nitrogen in the urine, as a measure of the quantity of proteid metabolized, uric acid, and other factors of interest in this connection.

The collection of data commenced on October 26, 1903. During some weeks the urine of each day was not analyzed by itself, but an aliquot part was taken from the 24 hours’ quantity, and at the end of a week the determinations were made on the mixture, thereby giving the average daily composition for the period. With Dr. Mendel, as in the writer’s case, there was no prescribing of food, but perfect freedom of choice. The appetite was satisfied each day, but with a gradual diminution of proteid food, especially of meat. Dr. Mendel appeared to accomplish the desired end best by keeping up a liberal allowance of non-nitrogenous food, and the total potential energy of the daily diet was not so greatly diminished as in the writer’s case. In other words, he appeared to need more food, but succeeded without great effort in reducing the proteid intake to nearly as low a level as in the preceding experiment. For the period of three months from January 4 to April 3, 1904, the average daily excretion of nitrogen amounted to 6.46 grams, which means the metabolism of 40.37 grams of proteid or albuminous food per day for this quarter of the year.

[53]

MENDEL.

Date. Body-weight. Urine.
Volume. 24 hours. Sp. Gr. Nitrogen. Uric Acid. P₂O₅.
1903 kilos c.c. grams gram grams
Oct. 26 76.2 1310 1019 10.53
27 75.0 1650 1016 13.46 0.580 1.90
28 74.5 915 1023 11.03
29 74.5 825 1025 11.48 0.629 1.87
30 74.6 1330 1018 13.17
31 74.5 1045 1021 12.37
Nov. 1 74.5 1030 1020 10.38 0.602 1.59
2 1080 1017 9.59
3 74.5 1058 1016 8.86 0.528 1.63
4 74.5 975 1019 8.66
5 74.5 1030 1021 8.90 0.514 1.83
6 1230 1015 8.11
7 74.6 1450 1016 8.18
8 74.0 970 1019 7.91 0.424 1.92
9 74.0 620 1028 7.72
10 74.0 543 1027 6.60 0.390 1.17
11 74.0 1160 1016 7.03
12 74.0 863 1024 5.37 0.422 1.52
13 74.0 1410 1015 8.12
14 74.0 1265 1017 8.04 0.494 1.94
16 74.0 760 1021 6.93
17 74.0 850 1021 7.34 0.393 1.50
18 74.0 757 1020 6.84 0.364
19 74.0 720 1025 7.35 0.456 1.25
20 74.0 655 1027 7.23 0.474
21 74.0 985 1021 7.44 0.397
22 74.5 590 1026 7.65 0.395 1.20
23 74.5 1100 7.00
daily
average
0.410
daily
average
1.72
daily
average
24 74.0 1200 1017
25 1030
26 74.0 850
27 935 1020
28 74.5 870 1021
29 74.5 993 1017
30 74.5 650 1023 7.28 0.480 1.80
Dec. 1 74.5 960 1018
2 790 1023
3 74.0 880 1023
4 1200 1016
[54] 5 74.0 930 1021
6 1080 1019
7 73.5 790 1023 7.63 0.438 1.91
8 73.5 965 1025
9 74.0 1130 1017
10 73.0 630 1031
11 73.0 925 1019
12 1395 1014
13 73.0 1010 1018
14 1030 1020 7.73
15 73.0 875 1021 7.88
16 625 1027 6.48 0.259 1.10
17 700 1027 7.60
18 880 1022 8.39
19 935 1020 7.68
20 1075 1019 7.35
21 523 1032 6.37
22 1455 1017 8.99
23 920 1021 8.33
24 725 1025 8.56
25 865 1024 8.51
26 710 1027 7.54
27 910 1026 7.64 0.438 1.16
28 830 1026
29 730 1027
30 670 1033
31 630
1904
Jan. 1 550
2 1030 1022
3 1020 1019
4 750 1021 5.63 0.436 1.41
5 1030 1016 5.31
6 73.0 815 1023 5.77
7 72.7 930 1019 6.02
8 73.5 1135 1017 5.72
9 72.2 995 1020 6.39
10 1175 1017 6.84
11 72.0 1050 1017 6.17 0.443 1.43
[55] 12 72.2 1230 1015 6.71
13 71.8 1250 1016 7.43
14 71.8 1140 1015 7.05
15 965 1019 5.99
16 860 1023 6.71
17 1030 1018 5.81
18 730 1028 5.74 0.465 1.48
19 825 1023 6.58
20 1035 1021 6.70
21 725 1030 6.96
22 815 1023 6.99
23 950 1018 6.27
24 71.6 790 1025 5.93
25 71.3 740 1027 5.33 0.429 1.29
26 600 1030 5.44
27 965 1020 6.89
28 1045 1015 6.33
29 895 1017 6.28
30 70.6 660 1027 6.53
31 905 1021 6.79
Feb. 1 71.7 695 1025 5.13 0.451 1.40
2 950 1023 6.84
3 1210 1019 8.10
4 71.5 985 1020 6.74
5 1155 1020 6.51
6 71.1 1035 1019 6.27
7 70.8 760 1025 6.98
8 70.5 800 1022 6.29
9 70.6 1150 1023 7.52 0.448
10 70.4 770 1022 6.75 0.318
11 69.2 520 1031 6.71 0.458
12 69.4 565 1033 8.24 0.390
13 69.4 560 1030 7.83 0.420
14 69.2 690 1027 7.99 0.447
15 69.5 680 1027 7.50 0.420
16 995 1019 6.86
17 1055 1018 5.63
18 1185 1015 6.11
19 712 1025 5.72
[56] 20 70.5 1000 1021 7.38
21 70.6 1235 1014 5.93
22 900 1018 6.16 0.488
23 70.2 840 1020 5.49
24 875 1017 5.83
25 70.5 1450 1018 8.09
26 70.2 1485 1015 6.68
27 1300 1013 5.93
28 69.2 735 1022 5.91
29 575 1030 6.21 0.462
Mar. 1 975 1019 7.51
2 70.5 1240 1015 7.29
3 1400 1013 6.63
4 70.2 1375 1016 7.34
5 69.9 1100 1017 7.06
6 70.0 960 1020 6.51
7 70.5 970 1017 5.53 0.413
8 70.9 1220 1015 5.56
9 70.9 1285 1015 5.70
10 1000 1020 6.24
11 70.8 1120 1017 5.98
12 1285 1015 6.55
13 70.4 1110 1015 5.79
14 70.0 690 1024 5.92 0.485
15 70.6 1240 1017 7.29
16 70.8 1450 1016 7.47
17 70.2 780 1022 6.41
18 1230 1012 6.57
19 70.1 780 1027 6.41
20 950 1020 6.21
21 70.7 1005 1020 6.36 0.527
22 70.9 1525 1014 6.50
23 70.6 825 1023 6.39
24 70.4 550 1029 6.07
25 1070 1018 6.93
26 70.8 1100 1017 6.40
27 70.6 1115 1016 5.82
28 70.2 1185 1015 6.22 0.389
29 70.5 1370 1014 6.58
[57] 30 70.3 1185 1016 6.26
31 70.3 1325 1013 5.96
Apr. 1 1060 1016 6.30
2 70.6 1115 1016 6.42
3 70.3 1290 1013 6.39
4 70.0 845 1022 6.44 0.356 1.54
5 1110 1020 6.39
6 1055 1022 7.53
7 575 1027 6.42
8 650 1031 6.94
9 795 1026 7.06
10 1230 1020 7.01
11 850 1021 5.61 0.419
12 1005 1018 6.66
13 695 1020 5.75
14 69.6 910 1027 5.79
15 70.1 1000 1018 6.42
16 70.9 1590 1016 6.30
17 70.8 1250 1015 5.25
18 70.5 985 1020 5.79 0.453
19 70.7 1230 1016 5.90
20 70.5 1485 1014 5.70
21 70.1 1125 1023 7.09
22 70.3 1665 1013 7.09
23 69.8 935 1023 6.06
24 69.7 1100 1018 6.07
25 69.6 935 1021 5.78 0.373
26 69.9 1000 1021 6.18
27 70.1 1295 1015 6.06
28 70.0 1425 1013 5.56
29 70.2 990 1022 6.24
30 70.2 1100 1021 7.32
May 1 70.0 1380 1014 5.96
2 69.8 1050 1016 5.35 0.260
3 69.8 700 1022 5.46
4 69.5 900 1019 6.48
5 69.6 750 1023 6.52
6 69.7 1120 1019 7.26
7 1010 1020 6.00
[58] 8 1165 1015 6.01
9 69.7 880 1020 5.38 0.408
10 70.0 935 1019 5.22
11 69.6 1050 1017 6.05
12 69.8 950 1020 6.15
13 1060 1020 6.62
14 69.5 1520 1015 6.47
15 69.3 1345 1014 5.65
16 69.0 1230 1015 5.09
17 68.4 775 1019 5.11
18 69.2 660 1021 6.06 0.325
19 68.6 905 1018 7.17
20 69.4 685 1022 6.33
21 69.1 1142 1018 6.78
22 69.5 1055 1019 5.70
23 69.6 1053 1018 5.75
24 69.8 895 1020 6.39
25 69.4 900 1018 6.05
26 69.7 725 1025 6.55
27 70.0 705 1026 7.36
28 71.0 1115 1020 8.23 0.476
29 1370 1016 7.83
30 69.7 740 1023 7.10
31 1135 1017 5.93
June 1 1300 1018 6.86
2 1420 1014 6.06
3 69.7 1447 1015 7.03
4 1383 1016 5.97
5 1530 1015 6.43
6 870 1023 5.53
7 1010 1013 4.91
8 815 1019 5.53
9 865 1019 6.59
10 69.7 1110 1015 6.36
11 1410 1017 5.95
12 69.1 1510 1014 6.07
13 1100 1016 5.94
14 1090 1018 5.43
15 1380 1017 6.46
[59] 16 70.0 1760 1014 6.55
17 1755 1013 6.63
18 1075 1026 6.06
19 70.0 1285 1016 6.55
20 585 1022 5.44
21 595 1024 6.93
22 655 1023 7.07
23 1230 1015 7.45
Daily aver. from Nov. 10, 1903. 1001 1020 6.53 0.419 1.46

From November 10, 1903, to June 23, 1904, a period of about seven months and a half, the average daily excretion of nitrogen through the urine was 6.53 grams. In other words, throughout this long period the average daily amount of proteid matter metabolized was 40.8 grams, only a little more than one-third the amount called for by the Voit standard. Until February, the body-weight gradually fell, but from the early part of February until the end of the experiment the body-weight remained practically stationary at 70 kilos. Dr. Mendel, however, from the necessities of his daily work in the laboratory was compelled to a much greater degree of physical activity than the subject of the preceding experiment, and consequently required a larger amount of non-nitrogenous food than the latter. Further, owing to his greater physical activity and the necessary variations in this daily activity, it was not so easy at first to attain equilibrium.

On February 9, a balance experiment of six days was commenced, with a careful comparison of the nitrogen intake and output. In the accompanying tables are shown all of the data. By scrutiny of these it will be seen that Dr. Mendel had adopted essentially a vegetarian diet. During this period of[60] six days, however, he was not in nitrogen equilibrium, neither was he strictly in body equilibrium, since there was a distinct tendency for the body to fall off in weight. In this connection it may be mentioned that there is always a tendency during a balance experiment of this character for the subject to eat less than he is ordinarily accustomed to, owing to the tediousness of weighing every particle of food consumed. Further, for the same reason, and to avoid excess of chemical work in the analysis of samples of food, he is inclined to limit his diet to a few articles and thereby unconsciously restricts his intake of food, sometimes disastrously so.

Tuesday, February 9, 1904.

Breakfast.—Bread 33 grams, sugar 20 grams, coffee and milk 210 grams.

Lunch.—Consommé 150 grams, sweet potato 170 grams, bread 135 grams, tomato 106 grams, coffee and milk 210 grams, sugar 20 grams.

Dinner.—Bread 75 grams, mashed potato 200 grams, string beans 91 grams, apple pie 282 grams, coffee and milk 210 grams, sugar 20 grams, water 100 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Bread 33 + 135 + 75 = 243 × 1.36 = 3.30 grams.
Sugar 20 + 20 + 20 = 60 × 0.00 = 0.00
Coffee (breakfast) 210 × 0.10 = 0.21
Consommé 150 × 0.38 = 0.57
Sweet potato 170 × 0.28 = 0.48
Tomato 106 × 0.19 = 0.20
Coffee (lunch) 210 × 0.15 = 0.32
Potato 200 × 0.36 = 0.72
String beans 91 × 0.26 = 0.24
Apple pie 282 × 0.49 = 1.38
Coffee (dinner) 210 × 0.099 = 0.21
Total nitrogen in food 7.63 grams.
Total nitrogen in urine 7.52
Fuel value of the food 2297 calories.

[61]

Wednesday, February 10, 1904.

Breakfast.—Bread 37 grams, sugar 20 grams, coffee and milk 210 grams.

Lunch.—Bread 110 grams, sugar 7 grams, milk 250 grams, apple fritters 90 grams.

Dinner.—Bread 37 grams, sugar 21 grams, baked beans 100 grams, cranberry sauce 125 grams, coffee and milk 210 grams, molasses candy 54 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Bread 37 + 110 + 37 = 184 × 1.65 = 3.04 grams.
Sugar 20 + 7 + 21 = 48 × 0.00 = 0.00
Coffee (breakfast) 210 × 0.12 = 0.25
Milk 250 × 0.55 = 1.37
Apple fritters 90 × 0.45 = 0.40
Baked beans 100 × 1.40 = 1.40
Cranberry sauce 125 × 0.04 = 0.05
Coffee (dinner) 210 × 0.11 = 0.23
Candy 54 × 0.06 = 0.03
Total nitrogen in food 6.77 grams.
Total nitrogen in urine 6.75
Fuel value of the food 1673 calories.

Thursday, February 11, 1904.

Breakfast.—Bread 40 grams, sugar 20 grams, coffee and milk 210 grams.

Lunch.—Bread 95 grams, sweet potato 130 grams, sugar 7 grams, milk 250 grams, peach preserve 93 grams.

Dinner.—Bread 90 grams, mashed potato 100 grams, tomato purée 135 grams, baked beans 75 grams, lemon pie 110 grams, coffee and milk 210 grams, sugar 21 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Bread 40 + 95 + 90 = 225 × 1.75 = 3.94 grams.
Sugar 20 + 7 + 21 = 48 × 0.00 = 0.00
Coffee (breakfast) 210 × 0.096 = 0.20
Sweet potato 130 × 0.31 = 0.40
Milk 250 × 0.51 = 1.27
[62]Peach preserve 93 × 0.09 = 0.08
Potato 100 × 0.36 = 0.36
Tomato purée 135 × 0.33 = 0.45
Baked beans 75 × 1.30 = 0.98
Lemon pie 110 × 0.61 = 0.67
Coffee (dinner) 210 × 0.13 = 0.27
Total nitrogen in food 8.62 grams.
Total nitrogen in urine 6.71
Fuel value of the food 1828 calories.

Friday, February 12, 1904.

Breakfast.—Bread 58 grams, sugar 21 grams, coffee and milk 210 grams.

Lunch.—Bread 120 grams, sugar 21 grams, custard 76 grams, milk 250 grams, coffee and milk 125 grams.

Dinner.—Bread 67.5 grams, sugar 21 grams, mashed potato 150 grams, lima beans 80 grams, coffee and milk 210 grams, apple dumpling 131 grams, molasses candy 27 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Bread 58 + 120 + 67.5 = 245.5 × 1.71 = 4.20 grams.
Sugar 21 + 21 + 21 = 63.0 × 0.00 = 0.00
Coffee (breakfast) 210.0 × 0.11 = 0.23
Custard 76.0 × 0.83 = 0.63
Milk 250.0 × 0.48 = 1.20
Coffee (lunch) 125.0 × 0.078 = 0.10
Potato 150.0 × 0.37 = 0.56
Lima beans 80.0 × 0.90 = 0.72
Coffee (dinner) 210.0 × 0.12 = 0.25
Apple dumpling 131.0 × 0.72 = 0.94
Candy 27.0 × 0.06 = 0.00
Total nitrogen in food 8.83 grams.
Total nitrogen in urine 8.24
Fuel value of the food 1929 calories.

[63]

Saturday, February 13, 1904.

Breakfast.—Bread 47.5 grams, sugar 28 grams, coffee and milk 210 grams.

Lunch.—Bread 57 grams, sugar 40 grams, sweet potato 135 grams, quince preserve 73 grams, apple turnovers 118 grams, coffee and milk 310 grams.

Dinner.—Bread 59 grams, mashed potato 175 grams, peas 80 grams, apple pie 141.5 grams, sugar 21 grams, coffee and milk 210 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Bread 47.5 + 57 + 59 = 164.0 × 1.64 = 2.69 grams.
Sugar 28 + 40 + 21 = 89.0 × 0.00 = 0.00
Coffee (breakfast) 210.0 × 0.11 = 0.23
Sweet potato 135.0 × 0.37 = 0.50
Quince preserve 73.0 × 0.047 = 0.03
Apple turnovers 118.0 × 0.96 = 1.13
Coffee (lunch) 310.0 × 0.15 = 0.47
Potato 175.0 × 0.37 = 0.65
Peas 80.0 × 0.96 = 0.77
Apple pie 141.5 × 0.43 = 0.61
Coffee (dinner) 210.0 × 0.11 = 0.23
Total nitrogen in food 7.31 grams.
Total nitrogen in urine 7.83
Fuel value of the food 2057 calories.

[64]

Sunday, February 14, 1904.

Breakfast.—Bread 50 grams, sugar 21 grams, banana 92.5 grams, coffee and milk 210 grams.

Lunch.—Bread 108.5 grams, sugar 28 grams, baked potato 165 grams, apple sauce 114 grams, coffee and milk 210 grams.

Dinner.—Bread 63 grams, sugar 28 grams, succotash 75 grams, mashed potato 200 grams, chocolate layer cake 80 grams, ice cream 73 grams, coffee and milk 210 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Bread 50 + 108.5 + 63 = 221.5 × 1.75 = 3.87 grams.
Sugar 21 + 28 + 28 = 77.0 × 0.00 = 0.00
Banana 92.5 × 0.002 = 0.19
Coffee (breakfast) 210.0 × 0.11 = 0.23
Baked potato 165.0 × 0.41 = 0.68
Apple sauce 114.0 × 0.029 = 0.03
Coffee (lunch) 210.0 × 0.10 = 0.21
Succotash 75.0 × 0.57 = 0.43
Mashed potato 200.0 × 0.37 = 0.74
Chocolate cake 80.0 × 0.75 = 0.60
Ice cream 73.0 × 0.58 = 0.42
Coffee (dinner) 210.0 × 0.11 = 0.23
Total nitrogen in food 7.63 grams.
Total nitrogen in urine 7.99
Fuel value of the food 2065 calories.

[65]

NITROGEN BALANCE.—Mendel.

Nitrogen
Taken in.
Output.
Nitrogen in Urine. Weight of Fæces (dry).
Feb. 9 7.63 grams. 7.52 grams.
10 6.77 6.75
11 8.62 6.71
12 8.83 8.24 53 ⎫ contain 5.84% N = 6.248 grm. N.
13 7.31 7.83 54 ⎭
14 7.63 7.99 39.2 contain 6.72% N = 2.634
146.2 8.882 grm. N.
46.79 45.04 + 8.882 grams nitrogen.
46.79 grams nitrogen. 53.92 grams nitrogen.
Nitrogen balance for six days = -7.13 grams.
Nitrogen balance per day = -1.19 grams.

Average Intake.

Calories per day 1975.
Nitrogen per day 7.83 grams.

[66]

In this balance period of six days the average daily intake of nitrogen was 7.83 grams, coupled with an average fuel value of the food per day of 1975 calories. This latter value was obviously too small for a man of Dr. Mendel’s body-weight, and doing the amount of physical work he was called upon to perform. Being on one’s feet in a laboratory six to eight hours a day, in addition to the ordinary activity of a vigorous man leading a strenuous life, necessitates the utilization and oxidation of considerable food material. The average daily output of nitrogen through the urine amounted to 7.50 grams, considerably above the average daily excretion for the seven months’ period. Still, under these conditions there was a minus balance of 7.13 grams of nitrogen for the six days’ period, indicating that the body was drawing upon its stock of proteid material to the extent of 1.19 grams of nitrogen per day. This does not necessarily mean that the body had need of that additional amount of proteid matter each day, but rather that the amount of total energy required was beyond the potential energy supplied by the food. There not being sufficient non-nitrogenous food at hand, the body was compelled to draw upon its own resources, and in so doing utilized some of its tissue proteid. This is made quite clear by the results of the second balance period shortly to be described.

It is evident, however, that while the body was not in nitrogen equilibrium for this particular period of six days, there must have been a general condition of both body and nitrogen equilibrium, otherwise the body-weight would not have remained practically stationary for so long a period as from February 7 to June 20.

Commencing May 18, a second nitrogen balance was attempted, in which, as in the preceding case, there was a careful comparison of income and output for seven days. There was as before a free choice of food, but it was essentially vegetable in character. A greater variety of foods was taken, however, and an effort was made to have the non-nitrogenous food somewhat more liberal in amount, though in as close harmony as possible with the desires of the appetite.

[67]

Wednesday, May 18, 1904.

Breakfast.—Banana 92 grams, bread rolls 28 grams, cream 50 grams, coffee 150 grams, sugar 21 grams.

Lunch.—Bread 66 grams, soup 150 grams, farina 154 grams, sweet potato 123 grams, beans 70 grams, syrup 50 grams, coffee 150 grams, cream 50 grams, sugar 14 grams.

Dinner.—Bread 42 grams, consommé 100 grams, spinach 100 grams, mashed potato 250 grams, apple pie 97 grams, coffee 150 grams, cream 50 grams, sugar 21 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Banana 92 × 0.23 = 0.212 grams.
Bread rolls 28 × 1.66 = 0.465
Cream 50 × 0.46 = 0.230
Coffee 150 × 0.066 = 0.099
Sugar 21 × 0.00 = 0.000
Bread 66 × 1.60 = 1.056
Soup 150 × 0.41 = 0.615
Farina 154 × 1.09 = 1.678
Sweet Potato 123 × 0.32 = 0.394
Beans 70 × 0.34 = 0.238
Syrup 50 × 0.024 = 0.012
Coffee 150 × 0.057 = 0.086
Cream 50 × 0.46 = 0.230
Sugar 14 × 0.00 = 0.000
Bread 42 × 1.80 = 0.756
Consommé 100 × 0.38 = 0.380
Spinach 100 × 0.53 = 0.530
Mashed potato 250 × 0.38 = 0.950
Apple pie 97 × 0.43 = 0.417
Coffee 150 × 0.06 = 0.090
Cream 50 × 0.46 = 0.230
Sugar 21 × 0.00 = 0.000
Total nitrogen in food 8.668 grams.
Total nitrogen in urine 6.060
Fuel value of the food 2359 calories.

[68]

Thursday, May 19, 1904.

Breakfast.—Banana 102 grams, bread rolls 50 grams, coffee 150 grams, cream 50 grams, sugar 21 grams.

Lunch.—Bread 57 grams, egg omelette 20 grams, hominy 137 grams, syrup 68 grams, potatoes 128 grams, coffee 100 grams, sugar 21 grams, cream 50 grams.

Dinner.—Tomato purée 200 grams, bread 24 grams, fried sweet potato 100 grams, spinach 70 grams, Indian meal 100 grams, syrup 25 grams, coffee 100 grams, sugar 21 grams, cream 40 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Banana 102 × 0.23 = 0.235 grams.
Bread rolls 50 × 1.54 = 0.770
Coffee 150 × 0.06 = 0.090
Cream 50 × 0.47 = 0.235
Sugar 21 × 0.00 = 0.000
Bread 57 × 1.60 = 0.912
Egg Omelette 20 × 1.58 = 0.316
Hominy 137 × 0.20 = 0.274
Syrup 68 × 0.024 = 0.016
Potatoes 128 × 0.49 = 0.627
Coffee 100 × 0.06 = 0.060
Cream 50 × 0.47 = 0.235
Sugar 21 × 0.00 = 0.000
Tomato purée 200 × 0.53 = 1.060
Bread 24 × 1.74 = 0.418
Sweet potato 100 × 0.38 = 0.380
Spinach 70 × 0.56 = 0.392
Indian meal 100 × 0.20 = 0.200
Syrup 25 × 0.024 = 0.006
Coffee 100 × 0.06 = 0.060
Sugar 21 × 0.00 = 0.000
Cream 40 × 0.47 = 0.188
Total nitrogen in food 6.474 grams.
Total nitrogen in urine 7.170
Fuel value of the food 2072 calories.

[69]

Friday, May 20, 1904.

Breakfast.—Sliced orange 140 grams, coffee 100 grams, cream 30 grams, sugar 21 grams.

Lunch.—Bread 28 grams, mashed potato 250 grams, lima beans 40 grams, coffee 100 grams, sugar 21 grams, cream 30 grams, fried hominy 115 grams, syrup 48 grams.

Dinner.—Bread 19 grams, consommé 150 grams, string beans 140 grams, mashed potato 250 grams, rice croquette 93 grams, cranberry jam 95 grams, coffee 100 grams, sugar 21 grams, cream 30 grams, syrup 25 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Sliced orange 140 × 0.20 = 0.280
Coffee 100 × 0.06 = 0.060
Cream 30 × 0.44 = 0.132
Sugar 21 × 0.00 = 0.000
Bread 28 × 1.71 = 0.479
Mashed potato 250 × 0.30 = 0.750
Lima beans 40 × 0.76 = 0.304
Coffee 100 × 0.06 = 0.060
Sugar 21 × 0.00 = 0.000
Cream 30 × 0.44 = 0.132
Fried hominy 115 × 0.57 = 0.656
Syrup 48 × 0.024 = 0.012
Bread 19 × 1.97 = 0.374
Consommé 150 × 0.59 = 0.885
String beans 140 × 0.36 = 0.504
Mashed potato 250 × 0.34 = 0.850
Rice croquettes 93 × 1.06 = 0.986
Cranberry jam 95 × 0.03 = 0.029
Coffee 100 × 0.06 = 0.060
Sugar 21 × 0.00 = 0.000
Cream 30 × 0.44 = 0.132
Syrup 25 × 0.024 = 0.006
Total nitrogen in food 6.691 grams.
Total nitrogen in urine 6.330
Fuel value of the food 1915 calories.

[70]

Saturday, May 21, 1904.

Breakfast.—Banana 153 grams, coffee 150 grams, sugar 21 grams, cream 30 grams.

Lunch.—Bread 25 grams, potato croquette 229 grams, Indian meal 109 grams, tomato 123 grams, syrup 48 grams, coffee 100 grams, sugar 14 grams, cream 20 grams.

Dinner.—Bread 31 grams, bean soup 100 grams, fried potato 200 grams, bacon 5 grams, lettuce-orange salad 47 grams, prunes 137 grams, coffee 100 grams, sugar 21 grams, cream 25 grams, banana 255 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Banana 153 × 0.23 = 0.352 grams.
Coffee 150 × 0.06 = 0.090
Sugar 21 × 0.00 = 0.000
Cream 30 × 0.43 = 0.129
Bread 25 × 1.82 = 0.455
Potato croquette 229 × 0.71 = 1.626
Indian meal 109 × 1.09 = 1.188
Tomato 123 × 0.17 = 0.209
Syrup 48 × 0.024 = 0.012
Coffee 100 × 0.06 = 0.060
Sugar 14 × 0.00 = 0.000
Cream 20 × 0.43 = 0.086
Bread 31 × 1.62 = 0.502
Bean soup 100 × 1.21 = 1.210
Fried potato 200 × 0.60 = 1.200
Bacon 5 × 3.05 = 0.153
Lettuce-orange salad 47 × 0.21 = 0.099
Prunes 137 × 0.16 = 0.219
Coffee 100 × 0.06 = 0.060
Sugar 21 × 0.00 = 0.000
Cream 25 × 0.43 = 0.108
Banana 255 × 0.23 = 0.587
Total nitrogen in food 8.345 grams.
Total nitrogen in urine 6.780
Fuel value of the food 2485 calories.

[71]

Sunday, May 22, 1904.

Breakfast.—Banana 220 grams, orange 60 grams, coffee 100 grams, sugar 21 grams, cream 25 grams.

Lunch.—Bread 35 grams, potato 300 grams, fried rice 160 grams, syrup 63 grams, ice cream 84 grams, coffee 100 grams, sugar 14 grams.

Dinner.—Cream of celery soup 100 grams, bread 21 grams, mashed potato 250 grams, spinach 40 grams, French fried potato 100 grams, strawberry short-cake 120 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Banana 220 × 0.23 = 0.506 grams.
Orange 60 × 0.20 = 0.120
Coffee 100 × 0.06 = 0.060
Sugar 21 × 0.00 = 0.000
Cream 25 × 0.45 = 0.113
Bread 35 × 1.57 = 0.550
Potato 300 × 0.30 = 0.900
Fried rice 160 × 0.75 = 1.200
Syrup 63 × 0.024 = 0.015
Ice cream 84 × 0.53 = 0.445
Coffee 100 × 0.06 = 0.060
Sugar 14 × 0.00 = 0.000
Cream of celery soup 100 × 0.33 = 0.330
Bread 21 × 1.91 = 0.401
Mashed potato 250 × 0.37 = 0.925
Spinach 40 × 0.55 = 0.220
French fried potato 100 × 0.57 = 0.570
Strawberry short-cake 120 × 0.50 = 0.600
Total nitrogen in food 7.015 grams.
Total nitrogen in urine 5.700
Fuel value of the food 2321 calories.

[72]

Monday, May 23, 1904.

Breakfast.—Banana 229 grams, coffee 125 grams, sugar 21 grams, cream 25 grams.

Lunch.—Bread 58 grams, apple sauce 125 grams, scrambled egg 15 grams, consommé 75 grams, fried potato 170 grams, rice croquette 197 grams, syrup 68 grams, coffee 100 grams, sugar 21 grams, cream 30 grams.

Dinner.—Bread 72.5 grams, vegetable soup 100 grams, potato croquette 198 grams, bacon 7 grams, string beans 120 grams, water ice 77 grams, coffee 100 grams, cream 30 grams, sugar 14 grams, banana 270 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Banana 229 × 0.23 = 0.527 grams.
Coffee 125 × 0.06 = 0.075
Sugar 21 × 0.00 = 0.000
Cream 25 × 0.45 = 0.113
Bread 58 × 1.63 = 0.945
Apple sauce 125 × 0.02 = 0.025
Scrambled egg 15 × 2.07 = 0.311
Consommé 75 × 0.65 = 0.488
Fried potato 170 × 0.60 = 1.020
Rice croquette 197 × 0.61 = 1.202
Syrup 68 × 0.024 = 0.016
Coffee 100 × 0.06 = 0.060
Sugar 21 × 0.00 = 0.000
Cream 30 × 0.45 = 0.135
Bread 72.5 × 1.75 = 1.269
Soup 100 × 0.70 = 0.700
Potato croquette 198 × 0.77 = 1.525
Bacon 7 × 3.28 = 0.230
String beans 120 × 0.22 = 0.264
Water ice 77 × 0.006 = 0.005
Coffee 100 × 0.06 = 0.060
Cream 30 × 0.45 = 0.135
Sugar 14 × 0.00 = 0.000
Banana 270 × 0.23 = 0.621
Total nitrogen in food 9.726 grams.
Total nitrogen in urine 5.750
Fuel value of the food 2756 calories.

[73]

Tuesday, May 24, 1904.

Breakfast.—Orange 100 grams, rolls 37 grams, rice 50 grams, syrup 25 grams, coffee 125 grams, sugar 21 grams, cream 50 grams.

Lunch.—Bread 77 grams, cream of celery soup 125 grams, mashed potato 270 grams, tomato sauce 50 grams, farina croquette 191 grams, syrup 78 grams, coffee 75 grams, cream 20 grams, sugar 7 grams.

Dinner.—Bread 49 grams, tomato soup 200 grams, French fried potato 200 grams, spinach 50 grams, farina croquette 276 grams, syrup 100 grams, coffee 100 grams, sugar 14 grams, cream 50 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Orange 100 × 0.20 = 0.200 grams.
Bread rolls 37 × 1.64 = 0.607
Rice 50 × 0.36 = 0.180
Syrup 25 × 0.024 = 0.006
Coffee 125 × 0.06 = 0.075
Sugar 21 × 0.00 = 0.000
Cream 50 × 0.45 = 0.225
Bread 77 × 1.66 = 1.278
Celery soup 125 × 0.48 = 0.600
Mashed potato 270 × 0.26 = 0.702
Tomato sauce 50 × 0.23 = 0.115
Farina croquette 191 × 0.74 = 1.413
Syrup 78 × 0.024 = 0.019
Coffee 75 × 0.06 = 0.045
Cream 20 × 0.45 = 0.090
Sugar 7 × 0.00 = 0.000
Bread 49 × 1.82 = 0.892
Tomato soup 200 × 0.19 = 0.380
French fried potato 200 × 0.46 = 0.920
Spinach 50 × 0.54 = 0.270
Farina croquette 276 × 0.76 = 2.098
Syrup 100 × 0.024 = 0.024
Coffee 100 × 0.06 = 0.060
Sugar 14 × 0.00 = 0.000
Cream 50 × 0.45 = 0.225
Total nitrogen in food 10.424 grams.
Total nitrogen in urine 6.390
Fuel value of the food 3229 calories.

[74]

NITROGEN BALANCE.—Mendel.

Nitrogen
Taken in.
Output.
Nitrogen in Urine. Weight of Fæces (dry).
May 18 8.668 grams. 6.06 grams. 14 grams.
19 6.474 7.17 39
20 6.691 6.33 30
21 8.345 6.78 83 contain 6.06% N = 5.03 grm. N.
22 7.015 5.70
23 9.726 5.75 38
24 10.424 6.39 57
95 contain 5.76% N = 5.47 grm. N.
10.50 grm. N.
57.343 44.18 + 10.50 grams nitrogen.
57.343 grams nitrogen. 54.68 grams nitrogen.
Nitrogen balance for seven days = +2.663 grams.
Nitrogen balance per day = +0.380 gram.

Average Intake.

Calories per day 2448.
Nitrogen per day 8.192 grams.

[75]

In this period of seven days the average daily intake of nitrogen was 8.192 grams, or only 0.36 gram per day more than in the first balance period, while the average fuel value of the food amounted to 2448 calories per day. Yet the average daily output of nitrogen through the urine for this period was 6.31 grams, or 1.2 grams per day less than in the first balance experiment. Further, under the conditions of this balance experiment, the body was laying up 0.380 gram of nitrogen per day, i. e., showing a plus balance of 2.66 grams of nitrogen for the seven days’ period. Again, it is to be noted that the average daily amount of nitrogen metabolized, 6.31 grams, was 0.22 gram less than the average daily nitrogen excretion for the entire seven months’ period, 6.53 grams. Evidently, this subject was quite able to maintain nitrogen equilibrium with a metabolism of only 6.31 grams of nitrogen per day, on a daily diet having a fuel value of about 2400 calories. Indeed, taking into account the amount of the plus nitrogen balance, it is evident that the daily food was somewhat in excess of the real requirements of the body, under the then existing conditions of body-weight and bodily activity.

Again, we would call attention to the thorough utilization of the food in this experiment, emphasizing at the same time the voluminous character of the diet, together with its largely vegetable nature. The contrast between the diet made use of by Dr. Mendel and that used by the subject of the first experiment is quite striking, since the latter employed a much more concentrated diet with an average fuel value of only 1600 calories. Yet with a total intake of 57.343 grams of nitrogen for the seven days of Dr. Mendel’s balance period, 10.5 grams only passed out through the rectum, or 18.3 per cent, while in the second nitrogen balance of the first subject, with the more concentrated diet, 17.1 per cent of the total ingested nitrogen appeared in the fæces. In view of the great divergence in the character and volume of the intake, it is rather remarkable there should be so little difference in the relative utilization of the two diets.

[76]

Finally, taking the average daily excretion of nitrogen through the kidneys from November 10 to June 23, as a measure of the nitrogen metabolized daily, viz., 6.53 grams, and taking the body-weight at 70 kilos, it is plain to see that the nitrogen metabolized per kilo of body-weight throughout this experiment was 0.093 gram, closely similar to the result obtained with the first subject. In other words, both of these subjects, though widely different in body-weight, under different degrees of physical activity, and living on different forms of diet, seemingly required for the maintenance of equilibrium essentially the same amount of nitrogen per kilo of body-weight; viz., with the first subject 0.0947 gram, if we take the lower figure of the last two months, and 0.093 gram with the second subject.

Regarding the fuel value of the daily food, Dr. Mendel with a body-weight of 70 kilos, during the second balance period, apparently utilized on an average 34.9 calories per kilo of body-weight daily, while the first subject, of 57 kilos body-weight, made use of only 28 calories per kilo. The fuel value of the daily food must, however, as is well known, vary greatly with differing degrees of physical activity, from which arises the necessity for corresponding variation in the amounts of non-nitrogenous foods ingested.

Dr. Frank P. Underhill, instructor in physiological chemistry in the Sheffield Scientific School, is another subject of experiment who volunteered to study on himself the effects of a lowered proteid intake. Prior to the experiment he was in the habit of eliminating from 16 to 16.5 grams of nitrogen per day through the kidneys, representing the usual 105 grams of proteid food metabolized.

Dr. Underhill, at the beginning of the experiment, July 1, 1903, was twenty-six years of age and weighed 67.6 kilos. For a period of two weeks, from July 14 to August 2, he gradually reduced the intake of proteid food as well as the total amount of food consumed, doing this in part by diminishing the quantity eaten at breakfast, and in smaller measure[77] at the two other meals of the day. During this period of two weeks, the urine and fæces were analyzed with the results shown in the accompanying table. Regarding the extent of proteid metabolism, it will be seen that the nitrogen content of the urine fell from 14.28 grams per day down to 5 to 6 grams per day. Having reached this level, the subject maintained it throughout the summer of 1903, occasional analyses being made to demonstrate the level of nitrogen excretion.

Date. Body-
weight.
Urine. Fæces. Total
Nitrogen.
Volume. Sp. Gr. Nitrogen. Moist. Dry. Nitrogen.
1903. c.c. grams. grams. grams. grams. grams.
July 14 67.6 1300 1018 14.28 156.0 30.5 1.59 15.8
15 67.6 1095 1020 11.72 70.0 17.0 0.80 12.52
16 67.1 860 1021 11.72 182.5 44.5 2.12 13.84
17 66.9 675 1022 9.39 134.0 43.0 2.05 11.44
18 66.3 865 1021 10.45 57.5 20.0 0.95 11.40
19 65.7 785 1021 10.34 170.0 41.0 1.95 12.29
20 65.7 740 1024 10.34 76.0 35.0 1.66 12.00
21 65.7 910 1017 11.61 96.0 32.0 1.52 13.13
22 65.7 900 1013 9.50 56.0 31.0 1.75 11.25
23 65.3 600 1017 8.65 41.0 14.0 0.79 9.35
24 65.0 640 1013 6.65 151.0 33.0 1.86 8.51
25 65.3 690 1012 6.01 86.0 29.0 1.63 7.64
26 65.3 410 1023 6.65 57.0 19.0 1.06 7.71
27 65.7 530 1017 6.75 202.0 33.0 1.86 8.61
28 65.7 610 1013 5.49 155.0 26.0 1.46 6.95
29 66.4 620 1017 5.96 121.0 26.0 1.46 7.42
30 66.3 700 1016 5.80 233.0 48.0 2.71 8.51
31 65.8 1265 1010 6.70 211.0 36.0 2.03 8.73
Aug. 1 65.3 1240 1009 6.23 172.0 23.0 1.29 7.52
2 65.3 760 1016 6.75 214.0 27.0 1.42 8.17
11 65.3 500 1017 6.44 152.0 22.0 1.34 7.78
12 65.3 405 1024 6.86 70.0 15.0 0.91 7.77
13 65.3 540 1019 6.23 90.0 10.0 0.61 6.84

[78]

In connection with the accompanying table of results, attention is called to the composition of the fæces with special reference to their content of nitrogen. The point to be emphasized is the gradual increase in the percentage content of fæcal nitrogen, associated with the changed diet and the general diminution of food intake. This is well illustrated by the following figures, giving the percentage of nitrogen in the dry fæces for the three periods of July 14-21, July 22-30, and August 11-13:

July 14-21, 4.77 per cent Nitrogen
July 22-30, 5.65
Aug. 11-13, 6.11

The diminished amount of fæcal discharge means naturally not only a smaller intake of food, but implies also a greater utilization of the food ingested, and as a result the increased percentage of nitrogen in the discharges shows itself because of the relatively larger preponderance of nitrogenous secretions from the intestinal tract.

The latter part of September, 1903, Dr. Underhill attempted to return to his original methods of living, but found difficulty in consuming the daily quantities of food he had formerly been in the habit of taking. From October 11 to October 25, 1903, however, he raised the consumption of proteid food to such a degree that the nitrogen excretion through the urine averaged from 10 to 12 grams per day. After this date he fell back to the lower proteid intake, and from that period to June 23, 1904, he maintained a low level of proteid metabolism without detriment to his bodily vigor, and, as he believes, with a distinct betterment.

The following tables of results extending from October 11, 1903, to June 23, 1904, show the data collected.

[79]

UNDERHILL.

Date. Body-weight. Urine.
Volume. 24 hours. Sp. Gr. Nitrogen. Uric Acid. P₂O₅.
1903 kilos c.c. grams gram grams
Oct. 11 65.4 1300 1015 10.37 0.611 1.72
12 700 1022 9.07
13 1050 1022 12.35 0.820 2.15
14 1400 1017 12.01
15 870 1020 11.48 0.671 1.76
16 1165 1013 12.09
17 840 1020 11.24
18 1150 1017 10.00 0.613 1.77
19 678 1022 7.79
20 1165 1018 10.76 0.603 1.60
21 1460 1017 11.91
22 950 1019 10.71 0.643 1.73
23 1165 1017 12.82
24 65.4 850 1025 12.49
25 850 1022 11.07 0.645 1.76
26 1025 1018 8.31
daily
average
0.465
daily
average
1.18
daily
average
27 775 1018
28 1140 1015
29 765 1020
30 860 1019
31 1150 1015
Nov. 1 750 1020 7.91 0.469 1.30
2 675 1022
3 955 1014
4 1270 1012
5 885 1015
6 770 1020
7 860 1021
8 775 1020 7.86 0.537 1.40
9 890 1018
10 1070 1018
11 755 1020
12 950 1023
13 1100 1017
14 980 1015
15 630 1020
16 65.0 700 1020 7.82 0.467 1.49
17 1000 1015
18 940 1018
19 770 1023
[80] 20 770 1025
21 790 1020
22 770 1021
23 590 1025 8.55 0.476 1.67
27 710 1024
28 1080 1017
29 760 1019
30 870 1018 7.72 0.506 1.43
Dec. 1 860 1017
2 1120 1015
3 1450 1009
4 720 1019
5 720 1019
6 510 1027
7 65.1 700 1018 7.36 0.474 1.44
8 650 1018
9 860 1013
10 975 1020
11 800 1021
12 830 1018
13 750 1019
14 860 1018 8.11 0.497 1.35
15 870 1019
16 880 1015
17 820
18 760 1021
19 860 1017
20 520 1023
21 1200 1014 7.18 1.05
22 65.0 510 1025
23 650 6.70 0.356 0.97
24 670
25 500
26 550
27 850
28 65.2 930 8.70 0.626 1.21
29 1200
30 750
31 1280
[81]Jan. 1 750
2 750
3 870
4 1230
5 720 1023 8.23 0.530 1.24
6 960 1020
7 760 1022
8 1000 1017
9 720 1025
10 65.1 730 1021
11 700 1016 7.74 0.618 1.20
12 650 1020
13 700 1024
14 660 1025
15 610 1025
16 710 1024
17 660 1022
18 770 1016 7.80 0.705 1.14
19 64.8 700 1022
20 1130 1018
21 830 1020
22 600 1019
23 480 1021
24 750 1019
25 680 1020 6.85 0.500 1.07
26 800 1018
27 800 1020
28 700 1020
29 64.4 1010 1014
30 980 1018
31 820 1015
Feb. 1 990 1015 7.98 0.535 1.24
2 660 1020
3 64.4 1060 1015
4 980 1017
5 970 1014
6 790 1019
7 1120 1015
8 715 1021 8.11
9 64.4 1225 1014 7.49 0.450
[82] 10 64.4 770 1018 6.14 0.505
11 64.5 715 1022 8.02 0.568
12 850 1021 8.82 0.539
13 490 1028 7.17 0.505
14 64.4 795 1020 7.73 0.543
15 780 1021 8.27 0.558
16 920 1023
17 660 1021
18 640 1027
19 730 1023
20 840 1027
21 700 1018
22 440 1025 7.47 0.556
23 600 1023
24 750 1022
25 830 1017
26 64.0 870 1021
27 910 1015
28 950 1014
29 600 1021 7.15 0.526
Mar. 1 680 1021
2 1120 1011
3 640 1021
4 1080 1016
5 1220 1034
6 890 1015
7 1000 1014 8.18 0.682
8 650 1020
9 750 1020
10 850 1018
11 950 1014
12 1000 1016
13 64.2 860 1019
14 840 1020 7.83 0.540
15 920 1016
16 750 1020
17 820 1017
18 1220 1012
19 920 1015
20 700 1022
[83] 21 900 1015 8.04 0.733
22 980 1013
23 990 1014
24 750 1020
25 820 1017
26 700 1021
27 910 1020
28 930 1017
30 900 1020
31 450 7.87 0.530 1.44
Apr. 1 500
2 420
3 600
4 950
5 930
6 980
7 600
8 980
9 800
10 810
11 65.2 940 1017 9.46 0.496
12 710 1024
13 750 1024
14 740 1020 7.55
15 590 1024 6.51
16 900 1016 7.51
17 1290 1009 5.11
18 65.2 590 1017 5.96 0.527
19 630 1024 6.39
20 670 1022 7.48
21 900 1021 8.10
22 980 1017 7.00
23 850 1019 7.60
24 640 1023 7.33
25 65.0 600 1021 8.23 0.490
26 610 1014 5.82
27 600 1023 7.27
28 970 1015 7.05
29 795 1017 5.91
30 700 1021 6.80
[84]May 1 795 1016 5.72
2 65.2 860 1017 6.50 0.344
3 1120 1016 6.92
4 1090 1015 6.54
5 580 1021 5.92
6 700 1020 7.29
7 895 1017 8.97
8 800 1016 7.30
9 65.2 895 1019 6.28 0.416
10 850 1019 6.27
11 960 1019 7.26
12 690 1022 6.29
13 990 1017 7.96
14 690 1022 7.21
15 900 1015 6.15
16 65.1 945 1014 5.10 0.364
17 1090 1016 6.15
18 620 1020 5.21
19 1110 1015 6.53
20 895 1016 6.12
21 810 1019 6.95
22 1110 1016 8.72
23 65.0 685 1020 7.07
24 560 1021 6.78
25 1090 1010 6.02 0.420
26 610 1017 5.97
27 790 1016 6.83
28 1100 1014 7.65
29 650 1021 6.12
30 65.0 630 1021 5.21
31 660 1018 5.07
June 1 65.1 920 1014 5.96
2 65.1 800 1013 5.81
3 65.0 950 1014 7.30
4 790 1015 6.78
5 780 1020 8.28
6 65.1 890 1015 6.89
7 720 1017 5.87
8 950 1015 5.93
9 1060 1014 4.96
[85] 10 940 1017 5.92
11 1050 1019 7.62
12 1000 1017 6.66
13 890 1021 7.26
14 1340 1016 6.91
15 1190 1015 6.86
16 720 1025 7.99
17 65.2 800 1017 7.25
18 820 1018 6.99
19 920 1014 6.18
20 890 1015 6.03
21 900 1016 6.37
22 760 1018 6.79
23 630 1020 6.06
Daily average from Oct. 26, 1903 833 1018 7.43 0.516 1.28

It will be seen by a study of the analytical data that Dr. Underhill had an average daily excretion of nitrogen through the kidneys from October 26, 1903, to June 23, 1904, of 7.43 grams. From October 26 to April 13, a period of nearly six months, the average daily excretion was 7.81 grams of nitrogen, while from the latter date to June 23 the average daily excretion amounted to 6.68 grams of nitrogen. Taking the body-weight at 65 kilos, the lower nitrogen figure would mean a metabolism of 0.102 gram of nitrogen per kilo of body-weight, closely akin to the figures obtained with the two preceding subjects.

An excretion of 6.68 grams of nitrogen corresponds to the metabolism of 41.75 grams of proteid matter, while the excretion of 7.43 grams of nitrogen implies the metabolism of 46.4 grams of proteid, being less than one-half the ordinarily accepted requirement for the healthy adult.

[86]

During this long period of eight months the body-weight was stationary, carrying with it the assumption that the body was in a condition of nitrogen equilibrium. It should be emphasized in connection with Dr. Underhill’s case, that throughout the entire period of eight months, and more, there was perfect freedom in the choice of food. Further, it will be noticed by a study of the dietary made use of in the balance experiments that Dr. Underhill did not reduce his nitrogen intake by any exclusion of meat. He practically made use of his ordinary diet, such as he had always been accustomed to, but with a decided diminution of the amount of proteid food, accompanied by a gradual reduction in the total amount of food consumed each day. His diet, therefore, was in no sense a vegetable diet. Meat was conspicuous in his daily food, but naturally in reduced quantities.

On February 9 a nitrogen balance was attempted, in which a careful comparison of the nitrogen content of all intake and output was made for a period of six days. By a study of the results of this balance period, shown in the accompanying tables, it will be noticed that not only was there no deficiency of nitrogen, but the body was laying on nitrogen at the rate of 0.158 gram per day. Further, it will be observed that the fuel value of the food per day averaged only a little over 2000 calories. Yet this amount of food, with its comparatively low fuel value, carried with it only 8.83 grams of nitrogen per day. Upon this quantity of food the body was able to maintain itself, with a little nitrogen to spare and with sufficient fuel value in the food to supply all the energy required for muscular contraction, mental effort, and the maintenance of body temperature.

[87]

Tuesday, February 9, 1904.

Breakfast.—Bread 22 grams, tea 146 grams.

Lunch.—Macaroni 129 grams, fried sweet potato 85.5 grams, bread 59 grams, butter 15 grams, fig cake with wine sauce 115 grams, sugar 15 grams, coffee 210 grams.

Dinner.—Bread 27.9 grams, beef 48 grams, potato 207.5 grams, butter 19 grams, pie 272 grams, coffee 210 grams, sugar 10 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Bread 22 + 59 + 27.9 = 108.9 × 1.61 = 1.753 grams.
Tea 146.0 × 0.018 = 0.026
Macaroni 129.0 × 0.87 = 1.122
Sweet potato 85.5 × 0.28 = 0.240
Butter 15 + 19 = 34.0 × 0.088 = 0.030
Fig cake 115.0 × 0.69 = 0.793
Sugar 15 + 10 = 25.0 × 0.00 = 0.000
Coffee (lunch) 210.0 × 0.09 = 0.207
Beef 48.0 × 2.64 = 1.267
Potatoes 207.5 × 0.36 = 0.747
Pie 272.0 × 0.49 = 1.332
Coffee (dinner) 210.0 × 0.15 = 0.315
Total nitrogen in food 7.832 grams.
Total nitrogen in urine 7.490
Fuel value of the food 2232 calories.

Wednesday, February 10, 1904.

Breakfast.—Bread 33 grams, tea 146 grams.

Lunch.—Bread 71 grams, butter 10.5 grams, apple fritters 119 grams, coffee 210 grams, sugar 21 grams.

Dinner.—Roast pork 80 grams, bread 55.7 grams, butter 27.8 grams, cranberry sauce 150 grams, coffee 210 grams, sugar 21 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Bread 33 + 71 + 55.7 = 159.7 × 1.65 = 2.635 grams.
Tea 146.0 × 0.075 = 0.109
Butter 10.5 + 27.8 = 38.3 × 0.088 = 0.033[88]
Apple fritters 119.0 × 0.45 = 0.535
Coffee (lunch) 210.0 × 0.11 = 0.231
Sugar 21 + 21 = 42.0 × 0.00 = 0.000
Roast pork 80.0 × 4.80 = 3.840
Cranberry sauce 150.0 × 0.04 = 0.060
Coffee (dinner) 210.0 × 0.11 = 0.231
Total nitrogen in food 7.674 grams.
Total nitrogen in urine 6.140
Fuel value of the food 1694 calories.

Thursday, February 11, 1904.

Breakfast.—Bread 38.7 grams, tea 146 grams.

Lunch.—Bread 97.5 grams, butter 31.5 grams, sweet potato 108.7 grams, spaghetti 82.5 grams, peaches 89.4 grams, coffee 210 grams, sugar 21 grams.

Dinner.—Bread 75 grams, butter 21.5 grams, roast beef 116 grams, lemon pie 188.5 grams, coffee 210 grams, sugar 21 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Bread 38.7 + 97.5 + 75 = 211.2 × 1.75 = 3.696 grams.
Tea 146.0 × 0.084 = 0.122
Butter 31.5 + 21.5 = 53.0 × 0.088 = 0.046
Sweet potato 108.7 × 0.31 = 0.336
Spaghetti 82.5 × 0.47 = 0.387
Peaches 89.4 × 0.09 = 0.080
Coffee (lunch) 210.0 × 0.096 = 0.201
Sugar 21 + 21 = 42.0 × 0.00 = 0.000
Roast beef 116.0 × 3.00 = 3.480
Lemon pie 188.5 × 0.61 = 1.149
Coffee (dinner) 210.0 × 0.13 = 0.273
Total nitrogen in food 9.770 grams.
Total nitrogen in urine 8.020
Fuel value of the food 2334 calories.

[89]

Friday, February 12, 1904.

Breakfast.—Bread 34 grams, tea 146 grams.

Lunch.—Bread 42 grams, butter 20 grams, codfish cake 72 grams, potato 100 grams, custard 100 grams, coffee 210 grams, sugar 21 grams.

Dinner.—Bread 46 grams, butter 25.5 grams, veal 53 grams, potato 75 grams, lima beans 50 grams, apple dumpling 120 grams, coffee 210 grams, sugar 21 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Bread 34 + 42 + 46 = 122.0 × 1.71 = 2.086 grams.
Tea 146.0 × 0.045 = 0.065
Butter 20 + 25.5 = 45.5 × 0.088 = 0.040
Codfish cake 72.0 × 1.57 = 1.130
Potato 100.0 × 0.41 = 0.410
Custard 100.0 × 0.83 = 0.830
Coffee (lunch) 210.0 × 0.078 = 0.163
Sugar 21 + 21 = 42.0 × 0.00 = 0.000
Veal 53.0 × 5.51 = 2.920
Potato 75.0 × 0.37 = 0.277
Lima beans 50.0 × 0.90 = 0.450
Apple dumpling 120.0 × 0.72 = 0.860
Coffee (dinner) 210.0 × 0.12 = 0.252
Total nitrogen in food 9.483 grams.
Total nitrogen in urine 8.820
Fuel value of the food 1735 calories.

Saturday, February 13, 1904.

Breakfast.—Bread 35 grams, tea 146 grams.

Lunch.—Bread 57.5 grams, butter 28 grams, sweet potato 100 grams, coffee 210 grams, sugar 21 grams, quince 105.5 grams, apple turnovers 153 grams.

Dinner.—Bread 35.5 grams, butter 11 grams, peas 70 grams, roast beef 50 grams, pie 169 grams, coffee 210 grams, sugar 21 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Bread 35 + 57.5 + 35.5 = 128.0 × 1.64 = 2.099 grams.
Tea 146.0 × 0.033 = 0.048
Butter 28 + 11 = 39.0 × 0.088 = 0.034[90]
Sweet potato 100.0 × 0.37 = 0.370
Coffee (lunch) 210.0 × 0.15 = 0.315
Sugar 21 + 21 = 42.0 × 0.00 = 0.000
Quince 105.5 × 0.047 = 0.049
Apple turnovers 153.0 × 0.96 = 1.468
Peas 70.0 × 0.96 = 0.672
Roast beef 50.0 × 3.22 = 1.610
Pie 169.0 × 0.43 = 0.726
Coffee (dinner) 210.0 × 0.11 = 0.231
Total nitrogen in food 7.622 grams.
Total nitrogen in urine 7.170
Fuel value of the food 2186 calories.

Sunday, February 14, 1904.

Breakfast.—Bread 31 grams, tea 146 grams.

Lunch.—Bread 70.5 grams, butter 29 grams, potato 123 grams, apple sauce 127.5 grams, coffee 210 grams, sugar 21 grams.

Dinner.—Bread 20.5 grams, butter 23 grams, chicken 101.5 grams, potato 80 grams, succotash 80 grams, chocolate cake 103 grams, ice cream 125.8 grams, coffee 210 grams, sugar 21 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Bread 31 + 70.5 + 20.5 = 122.0 × 1.75 = 2.135 grams.
Tea 146.0 × 0.063 = 0.091
Butter 29 + 23 = 52.0 × 0.088 = 0.045
Potato 123.0 × 0.41 = 0.504
Apple sauce 127.5 × 0.029 = 0.037
Coffee (lunch) 210.0 × 0.10 = 0.210
Sugar 21 + 21 = 42.0 × 0.00 = 0.000
Chicken 101.5 × 5.08 = 5.150
Potato 80.0 × 0.37 = 0.296
Succotash 80.0 × 0.57 = 0.456
Chocolate cake 103.0 × 0.75 = 0.772
Ice cream 125.8 × 0.58 = 0.729
Coffee (dinner) 210.0 × 0.11 = 0.231
Total nitrogen in food 10.656 grams.
Total nitrogen in urine 7.730
Fuel value of the food 2231 calories.

[91]

NITROGEN BALANCE.—Underhill.

Nitrogen
Taken in.
Output.
Nitrogen in Urine. Weight of Fæces (dry).
Feb. 9 7.832 grams. 7.49 grams. 9.5 grams.
10 7.674 6.14
11 9.770 8.02 32.0
12 9.483 8.82 9.5
13 7.622 7.17 28.0
14 10.656 7.73 24.0
103.0 grams contain
6.52% N.
53.037 45.37 + 6.715 grams nitrogen.
53.037 grams nitrogen. 52.085 grams nitrogen.
Nitrogen balance for six days = +0.952 gram.
Nitrogen balance per day = +0.158 gram.

Average Intake.

Calories per day 2068.
Nitrogen per day 8.83 grams.

[92]

On June 1, near the close of the experiment, a second nitrogen balance was attempted, with a view to seeing if under the existing conditions of life and activity it was possible to reduce the fuel value of the food, and at the same time diminish in still greater measure the quantity of proteid food taken. The results of this trial are seen in the accompanying tables, where for four days a careful comparison of output and intake is shown. It will be observed from these tables that the average fuel value of the food per day was reduced to 1785 calories, and that the average intake of nitrogen was restricted to 6.73 grams per day. The balance shown is a minus balance, although the deficiency per diem is not large. It is very obvious that both the nitrogen and fuel value of the food can be reduced considerably below the average maintained during the period of the first balance, but not to the degree attempted in the second balance, and secure nitrogen or body equilibrium. It will be noted in this last nitrogen balance, that the average daily output of nitrogen through the urine amounted to 6.46 grams, while the average nitrogen intake was 6.73 grams. The fuel value of the food, however, averaged only 1785 calories per day. It is quite evident, if the non-nitrogenous food had not been reduced quite so much, that a plus nitrogen balance would have been obtained. Still, it is obvious that under the conditions of life and activity, this subject needed to metabolize only about 40 grams of proteid per day, with the total fuel value of his food equal to about 2000 calories, in order to secure both body and nitrogen equilibrium. Here, again, we have an illustration of the possibility of physiological economy which shows itself in a reduction of the daily proteid food more than 50 per cent, with a reduction of the non-nitrogenous food fully 30 per cent, and with maintenance of health, strength and vigor equal, if not superior, to that which the subject has ever experienced.

[93]

Wednesday, June 1, 1904.

Breakfast.—Champagne wafer 21.5 grams, tea 146 grams, sugar 15 grams.

Dinner.—Bread 67.4 grams, butter 15.1 grams, beefsteak 55.5 grams, potato 128 grams, asparagus 103.5 grams, tea 146 grams, sugar 15 grams, banana 83.5 grams.

Supper.—Bread 15.7 grams, butter 11.8 grams, banana and nuts 106 grams, crullers 90.2 grams, coffee 145 grams, sugar 15 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Champagne wafer 21.5 × 0.64 = 0.138 gram.
Tea 146.0 × 0.015 = 0.022
Sugar 15 + 15 + 15 = 45.0 × 0.000 = 0.000
Bread 67.4 + 15.7 = 83.1 × 1.46 = 1.212
Butter 15.1 + 11.8 = 26.9 × 0.10 = 0.027
Banana 83.5 × 0.28 = 0.192
Beefsteak 55.5 × 4.72 = 2.620
Potato 128.0 × 0.32 = 0.410
Asparagus 103.5 × 0.35 = 0.362
Tea 146.0 × 0.033 = 0.048
Crullers 90.2 × 1.04 = 0.938
Banana and nuts 106.0 × 0.69 = 0.731
Coffee 145.0 × 0.060 = 0.087
Total nitrogen in food 6.787 grams.
Total nitrogen in urine 5.960
Fuel value of the food 1913 calories.

Thursday, June 2, 1904.

Breakfast.—Bread 30 grams, tea 146 grams, sugar 15 grams.

Dinner.—Clam chowder 270.5 grams, bread 64 grams, butter 14.5 grams, lobster 36.5 grams, Saratoga chips 15 grams, caramel custard 79 grams, tea 146 grams, sugar 15 grams.

Supper.—Bread 35.2 grams, butter 13.8 grams, pineapple 148.7 grams, crullers 84.8 grams, tea 140 grams, sugar 15 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Bread 30.0 × 1.46 = 0.438 gram.
Tea 146.0 × 0.045 = 0.066
Sugar 15 + 15 + 15 = 45.0 × 0.00 = 0.000
[94]Bread 64 + 35.2 = 99.2 × 1.44 = 1.428
Butter 14.5 + 13.8 = 28.3 × 0.10 = 0.028
Clam chowder 270.5 × 0.34 = 0.920
Lobster 36.5 × 3.73 = 1.361
Saratoga chips 15.0 × 0.97 = 0.146
Caramel custard 79.0 × 0.77 = 0.608
Tea 146.0 × 0.036 = 0.053
Tea 140.0 × 0.036 = 0.050
Pineapple 148.7 × 0.054 = 0.080
Crullers 84.8 × 1.04 = 0.882
Total nitrogen in food 6.060 grams.
Total nitrogen in urine 5.810
Fuel value of the food 1921 calories.

Friday, June 3, 1904.

Breakfast.—Bread 31 grams, tea 146 grams.

Dinner.—Fried ham 61 grams, asparagus 124.2 grams, baked potato 85 grams, bread 29 grams, butter 23.5 grams, tea 140 grams, sugar 15 grams, pineapple 74.8 grams.

Supper.—Bread 34 grams, butter 17.8 grams, pineapple 158.5 grams, tomato 132.5 grams, cup cake 121 grams, tea 140 grams, sugar 15 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Bread 31 + 20 + 34 = 94.0 × 1.44 = 1.354 grams.
Tea 146.0 × 0.039 = 0.057
Fried ham 61.0 × 4.90 = 2.989
Asparagus 124.2 × 0.50 = 0.621
Baked potato 85.0 × 0.55 = 0.468
Butter 23.5 + 17.8 = 41.3 × 0.10 = 0.041
Tea 140.0 × 0.027 = 0.038
Sugar 15 + 15 = 30.0 × 0.000 = 0.000
Pineapple 74.8 + 158.5 = 233.3 × 0.065 = 0.152
Tea 140.0 × 0.054 = 0.076
Tomato 132.5 × 0.150 = 0.199
Cup cake 121.0 × 0.85 = 1.029
Total nitrogen in food 7.024 grams.
Total nitrogen in urine 7.300
Fuel value of the food 2011 calories.

[95]

Saturday, June 4, 1904.

Breakfast.—Bread 32 grams, tea 140 grams.

Dinner.—Hash 133 grams, peas 151.5 grams, bread 61.4 grams, butter 16.1 grams, custard 150 grams, sugar 15 grams, tea 140 grams.

Supper.—Bread 62.5 grams, butter 17 grams, tea 140 grams, sugar 15 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Bread 32.0 × 1.44 = 0.461 gram.
Tea 140.0 × 0.021 = 0.029
Hash 133.0 × 1.50 = 1.995
Peas 151.5 × 1.04 = 1.576
Bread 61.4 + 62.5 = 123.9 × 1.47 = 1.821
Butter 16.1 + 17 = 33.1 × 0.10 = 0.033
Custard 150.0 × 0.78 = 1.170
Sugar 15 + 15 = 30.0 × 0.00 = 0.000
Tea 140.0 × 0.033 = 0.046
Tea 140.0 × 0.030 = 0.042
Total nitrogen in food 7.173 grams.
Total nitrogen in urine 6.780
Fuel value of the food 1297 calories.

[96]

NITROGEN BALANCE.—Underhill.

Nitrogen
Taken in.
Output.
Nitrogen in Urine. Weight of Fæces (dry).
June 1 6.787 grams. 5.96 grams. 10 grams.
2 6.060 5.81 10
3 7.024 7.30 25
4 7.173 6.78 6
51 grams contain
5.81 % N.
27.044 25.85 + 2.963 grams nitrogen.
27.044 grams nitrogen. 28.813 grams nitrogen.
Nitrogen balance for four days = -1.760 grams.
Nitrogen balance per day = -0.442 grams.

Average Intake.

Calories per day 1785.
Nitrogen per day 6.73 grams.

[97]

Dr. Arthur L. Dean, Instructor in Plant Physiology in the Sheffield Scientific School, twenty-five years of age, and weighing 64 kilos, likewise became a subject of study in this investigation. He is a man of strong physique, and as an undergraduate student at Harvard University trained for various athletic events. He began on the experiment October 13, 1903, and continued until April 3, 1904. From October 13th to October 27 he followed his usual dietary habits, simply reducing in some measure the amount of food consumed. During this period of fifteen days, the average excretion of nitrogen per day through the kidneys was about 12 grams. On the 28th of October he began to reduce in still greater measure the amount of proteid food eaten, and gradually diminished the extent of his proteid metabolism, although not to the same degree as the preceding subjects. He had full freedom of choice in the character and quantity of his diet, but his food was characterized by a predominance of vegetable matter, with an almost complete exclusion of meat.

For a period of nearly six months, or more exactly, from October 28 to April 3, the average daily output of nitrogen through the kidneys amounted to 8.99 grams, while the average daily output of uric acid was 0.386 gram. This daily excretion of 8.99 grams of nitrogen implies a metabolism of 56.18 grams of proteid. This, to be sure, means a reduction in proteid metabolism of about 50 per cent, as compared with the Voit and other standards, but does not show an economy equal to that practised by the preceding subjects. It is to be noted, however, in Dr. Dean’s case, that the body-weight did not show at any time in the experiment a tendency to diminish. In fact, all through the experiment his body-weight was a little higher than at the beginning.

[98]

DEAN.

Date. Body-weight. Urine.
Volume. 24 hours. Sp. Gr. Nitrogen. Uric Acid. P₂O₅.
1903 kilos c.c. grams gram grams
Oct. 13 63.2 1100 1017 10.63 0.323 2.38
14 1050 1020 9.83
15 1390 1018 14.93 0.432 1.98
16 1370 1017 11.26
17 1350 1019 11.18
18 1670 1017 11.62 0.490 2.51
19 63.2 1075 1018 10.19
20 1260 1015 9.98 0.483 1.88
21 1350 1020 13.04
22 1405 1015 11.38 0.431 2.07
23 1240 1020 11.98
24 1200 1023 11.16
25 1365 1018 11.97 0.395 2.02
26 1195 1020 10.75
27 1240 1021 11.90 0.477 1.97
28 1704 9.29
daily
average
0.398
daily
average
1.69
daily
average
29 1105
30 64.5 1180
31 910
Nov. 1 710
2 1540 8.54 0.354 1.65
3 1250
4 1300
5 975
6 1150
8 64.6 1192 1025 10.86 0.493
9 845 8.84 0.368 1.85
10 1255
11 1245
12 1540
13 940
14 1300
15 1065
16 64.5 1165 9.45
17 910
18 840 10.59 0.444
19 1720 1012 10.32 0.331 1.95
20 640 1022 8.60 0.336 1.75
[99] 21 1310 1016 9.27 0.378
22 720 1026 8.42 0.415
23 64.7 900 8.22 0.322 1.74
24 1520
25 1095
26 710
27 700
28 1140
29 1200
30 820 8.15 0.362 1.68
Dec. 1 1335
2 64.5 940
3 970
4 1240
5 1190
6 720
7 1160 9.12 0.342 2.11
8 960
9 850
10 935
11 945
12 1425
13 64.3 1065
14 770 9.08
15 790
30 1230 1017 8.60 0.375 1.80
31 66.1 1525 1020
1904
Jan. 1 1010 1021
2 1270 1020
3 1230 1020
4 820 8.42 0.338 1.76
5 1425 1018
6 1100 1021
7 1025 1021
8 760
9 1450 1019
10 65.8 1410 1016
11 1030 1017 8.51 0.428
[100] 12 65.0 830 1023
13 790 1025
14 1070 1020
15 1300 1019
16 925 1025
17 1100 1023
18 850 1025 8.23
19 1120 1019
20 1005 1020
21 1270 1020
22 980 1020
23 650
24 980 1024
25 65.5 1000 8.85 0.395 1.67
26 940
27 1350
28 840
29 675
30 740
31 1160 1017
Feb. 1 700 8.22 0.381 1.19
2 860
3 925
4 590
5 835
6 935
7 930
8 1035 1017 9.00
9 64.1 800 1027 8.64 0.432
10 940 1020 8.29 0.314
11 720 1030 8.55 0.364
12 860 1023 9.93 0.348
13 980 1022 8.87 0.379
14 63.9 1285 1022 8.33 0.385
15 910 9.30 0.301
16 1210
17 1455
18 1000 1022
[101] 19 1420
20 1050
21 64.5 1365
22 765 9.685 0.423
23 1070
24 1080
25 1495
26 970
28 750
29 725 10.31 0.410
Mar. 1 1100
2 990 1024
3 1180
4 1100
5 1010
6 970
7 790 8.99 0.433
8 64.4 670
9 840
10 1110
11 1090
12 755
13 1220
14 745 8.24 0.368
15 1030
16 1040
17 1080
18 1390
19 795
20 64.0 840
21 720 9.26 0.545
22 970
23 1200
24 845
25 1000
26 1180
27 1750
28 820 9.59 0.409
[102] 29 710
30 1100
31 770
Apr. 1 1250
2 885
3 65.0 630
Daily average from Oct. 28, 1903 1035 1021 8.99 0.386 1.73

On February 9, a nitrogen balance was attempted, when for a period of six days a careful comparison of intake and output of nitrogen was made. The results show that while during this period of six days 52.999 grams of nitrogen were ingested, there was an output through the urine and fæces of 61.13 grams of nitrogen, thus indicating a minus balance for this period of 1.355 grams of nitrogen per day. The average daily intake of nitrogen was 8.83 grams. The average daily output of nitrogen through the kidneys was 8.77 grams, being 0.22 gram less than the average daily excretion through the kidneys for the six months’ period. The fuel value of the food for this period averaged 2529 calories per day. The nitrogen balance, however, is so strikingly a minus balance that we are forced to conclude the above quantities of food were not quite sufficient to meet the needs of the body under the then existing conditions. Still, the fact that the body-weight during the entire period of six months showed no tendency downward implies that during this longer period the body must have been essentially in nitrogen equilibrium, under conditions whereby there was a metabolism of only 56 grams of proteid per day. As before stated, this means a physiological economy, as contrasted with existing standards, of about 50 per cent in proteid[103] food. So far as was to be seen, the bodily strength and vigor of the subject, like his body-weight, were fully maintained under the restricted diet, but, for some reason, he did not apparently take as kindly to a reduction of proteid food, and did not accomplish so great a lowering in the rate of proteid metabolism.

Following are the data of the balance experiment:

Tuesday, February 9, 1904.

Breakfast.—Coffee 210 grams, bread 38.5 grams, oatmeal 127 grams, cream 92 grams, sugar 20 grams.

Lunch.—Bread 63.5 grams, butter 12.5 grams, potato 155 grams, consommé 150 grams, stewed tomato 109 grams, coffee 210 grams, sugar 20 grams, pudding 85 grams.

Dinner.—Roast beef 17.5 grams, potato 177 grams, bread 39.1 grams, butter 12 grams, string beans 110 grams, apple pie 237.6 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Coffee 210.0 × 0.10 = 0.210 grams.
Bread 38.5 + 63.5 + 39.1 = 141.1 × 1.36 = 1.918
Oatmeal 127.0 × 0.64 = 0.812
Cream 92.0 × 0.40 = 0.368
Butter 12.5 + 12 = 24.5 × 0.088 = 0.021
Potato 155.0 × 0.28 = 0.434
Consommé 150.0 × 0.38 = 0.570
Tomato 109.0 × 0.19 = 0.207
Sugar 20 + 20 = 40.0 × 0.00 = 0.000
Pudding 85.0 × 0.69 = 0.586
Roast beef 17.5 × 2.64 = 0.462
Potato 177.0 × 0.36 = 0.637
String beans 110.0 × 0.26 = 0.286
Apple pie 237.6 × 0.49 = 1.164
Coffee 210.0 × 0.099 = 0.208
Total nitrogen in food 7.883 grams.
Total nitrogen in urine 8.640
Fuel value of the food 2576 calories.

[104]

Wednesday, February 10, 1904.

Breakfast.—Coffee 210 grams, bread 31.8 grams, cream 50 grams, sugar 40 grams, oatmeal 155 grams.

Lunch.—Bread 77 grams, butter 14.5 grams, apple fritters 193.5 grams, coffee 210 grams, sugar 20 grams.

Dinner.—Bread 82 grams, butter 20 grams, cranberries 150 grams, baked beans 150 grams, coffee 210 grams, sugar 32 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Coffee 210.0 × 0.12 = 0.252 grams.
Bread 31.8 + 77 + 82 = 190.8 × 1.65 = 3.148
Cream 50.0 × 0.47 = 0.235
Sugar 40 + 20 + 32 = 92.0 × 0.00 = 0.000
Oatmeal 155.0 × 0.60 = 0.930
Butter 14.5 + 20 = 34.5 × 0.088 = 0.030
Fritters 193.5 × 0.45 = 0.870
Coffee 210.0 × 0.11 = 0.231
Cranberries 150.0 × 0.04 = 0.060
Baked beans 150.0 × 1.40 = 2.100
Coffee 210.0 × 0.11 = 0.231
Total nitrogen in food 8.087 grams.
Total nitrogen in urine 8.290
Fuel value of the food 2145 calories.

Thursday, February 11, 1904.

Breakfast.—Bread 49 grams, oatmeal 185.7 grams, cream 64 grams, coffee 210 grams, sugar 35 grams.

Lunch.—Bread 111.8 grams, butter 40.5 grams, sweet potato 287 grams, peach preserve 109.3 grams.

Dinner.—Tomato purée 99 grams, bread 94.5 grams, butter 21.5 grams, beans 138 grams, lemon pie 155 grams, coffee 210 grams, sugar 21 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Bread 49 + 111.8 + 94.5 = 255.3 × 1.75 = 4.467 grams.
Oatmeal 185.7 × 0.40 = 0.742
Cream 64.0 × 0.49 = 0.313
[105]Coffee 210.0 × 0.096 = 0.201
Sugar 35 + 21 = 56.0 × 0.00 = 0.000
Butter 40.5 + 21.5 = 62.0 × 0.088 = 0.054
Sweet potato 287.0 × 0.31 = 0.889
Peach preserve 109.3 × 0.09 = 0.098
Tomato purée 99.0 × 0.33 = 0.326
Beans 138.0 × 1.30 = 1.794
Lemon pie 155.0 × 0.61 = 0.945
Coffee 210.0 × 0.13 = 0.273
Total nitrogen in food 10.102 grams.
Total nitrogen in urine 8.550
Fuel value of the food 2854 calories.

Friday, February 12, 1904.

Breakfast.—Oatmeal 192.3 grams, cream 75.5 grams, bread 41.6 grams, coffee 210 grams, sugar 20 grams.

Lunch.—Bread 64.1 grams, butter 14 grams, fish cakes 60 grams, potato 200 grams, custard 107.3 grams.

Dinner.—Bread 60 grams, butter 15 grams, lima beans 100 grams, potato 150 grams, apple dumpling 259 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Oatmeal 192.3 × 0.52 = 0.999 grams.
Cream 75.5 × 0.50 = 0.377
Bread 41.6 + 64.1 + 60 = 165.7 × 1.71 = 2.833
Coffee 210.0 × 0.11 = 0.231
Sugar 20.0 × 0.00 = 0.000
Butter 14 + 15 = 29.0 × 0.088 = 0.025
Fish cakes 60.0 × 1.57 = 0.942
Potato 200.0 × 0.41 = 0.820
Custard 107.3 × 0.83 = 0.890
Lima beans 100.0 × 0.90 = 0.900
Potato 150.0 × 0.37 = 0.555
Apple dumpling 259.0 × 0.72 = 1.864
Total nitrogen in food 10.436 grams.
Total nitrogen in urine 9.930
Fuel value of the food 2363 calories.

[106]

Saturday, February 13, 1904.

Breakfast.—Oatmeal 150 grams, cream 42 grams, sugar 31 grams, bread 31 grams, coffee 210 grams.

Lunch.—Bread 36 grams, sweet potato 222 grams, butter 17 grams, quince preserve 81.5 grams, apple turnover 154.5 grains.

Dinner.—Potato 175 grams, bread 62 grams, butter 15 grams, peas 100 grams, apple pie 177 grams, coffee 210 grams, sugar 21 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Oatmeal 150.0 × 0.43 = 0.645 grams.
Cream 42.0 × 0.50 = 0.210
Sugar 31 + 21 = 52.0 × 0.00 = 0.000
Bread 31 + 36 + 62 = 129.0 × 1.64 = 2.115
Coffee 210.0 × 0.11 = 0.231
Sweet potato 222.0 × 0.37 = 0.821
Butter 17 + 15 = 32.0 × 0.088 = 0.028
Quince preserve 81.5 × 0.047 = 0.038
Apple turnover 154.5 × 0.96 = 1.483
Potato 175.0 × 0.37 = 0.647
Peas 100.0 × 0.96 = 0.960
Apple pie 177.0 × 0.43 = 0.761
Coffee 210.0 × 0.11 = 0.231
Total nitrogen in food 8.170 grams.
Total nitrogen in urine 8.870
Fuel value of the food 2606 calories.

[107]

Sunday, February 14, 1904.

Breakfast.—Quaker oats 150 grams, bread 42.5 grams, coffee 210 grams, sugar 31 grams, banana 88.2 grams, cream 87.6 grams.

Lunch.—Bread 87.3 grams, butter 28.7 grams, potato 210 grams, apple sauce 116.5 grams.

Dinner.—Bread 51.5 grams, butter 12.2 grams, sugar 21 grams, potato 150 grams, succotash 100 grams, chocolate cake 122.5 grams, vanilla ice 110.7 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Quaker oats 150.0 × 0.46 = 0.690 grams.
Bread 42.5 + 87.3 + 51.5 = 181.3 × 1.75 = 3.172
Coffee 210.0 × 0.11 = 0.231
Sugar 31 + 21 = 52.0 × 0.00 = 0.000
Banana 88.2 × 0.20 = 0.176
Cream 87.6 × 0.50 = 0.438
Butter 28.7 + 12.2 = 40.9 × 0.088 = 0.035
Potato 210.0 × 0.41 = 0.861
Apple sauce 116.5 × 0.029 = 0.033
Potato 150.0 × 0.37 = 0.555
Succotash 100.0 × 0.57 = 0.570
Chocolate cake 122.5 × 0.75 = 0.918
Vanilla ice 110.7 × 0.58 = 0.642
Total nitrogen in food 8.321 grams.
Total nitrogen in urine 8.330
Fuel value of the food 2635 calories.

[108]

NITROGEN BALANCE.—Dean.

Nitrogen
Taken in.
Output.
Nitrogen in Urine. Weight of Fæces (dry).
Feb. 9 7.883 grams. 8.64 grams.
10 8.087 8.29
11 10.102 8.55 18 grams.
12 10.436 9.93 18
13 8.170 8.87 80
14 8.321 8.33 58
174 grams contain
4.90% N.
52.999 52.61 + 8.52 grams nitrogen.
52.999 grams nitrogen. 61.13 grams nitrogen.
Nitrogen balance for six days = -8.131 grams.
Nitrogen balance per day = -1.355 grams.

Average Intake.

Calories per day 2529.
Nitrogen per day 8.83 grams.

[109]

Mr. George M. Beers, Clerk in the Treasurer’s office of the Sheffield Scientific School, became a subject of study in January, 1903. Mr. Beers was thirty-eight years of age, and had always enjoyed fairly good health, although of somewhat frail physique. His occupation has always been indoor work as accountant, etc. His body-weight was 61 kilos.

Mr. Beers came to the writer for advice as to possible ways of improving his general health, and when it was learned that he was in the habit of eating large amounts of meat, the suggestion was made to him that it might be wise to ascertain the effect of a diminished quantity of proteid food, and as a result of this advice Mr. Beers began to cut down the amount of meat consumed daily. The effect of this abstention from meat was so noticeable that voluntarily all meat was withdrawn from his diet. With this change in dietary habits there came about a loss of body-weight, which, however, was soon regained.

Commencing with May 14, 1903, the amount of nitrogen excreted from the kidneys was determined from time to time, but not each day, since it was very soon found that Mr. Beers showed great regularity in his dietary habits, and a corresponding regularity in the composition of the output. This regularity was due in large measure to the fact that the subject became, for the time at least, practically a vegetarian. The beneficial effects noted in his own experience with abstention from meat led to his voluntarily excluding it from his daily diet, so that from January, 1903, to June, 1904, the subject practically tasted meat, fish, or eggs on only four occasions, namely, the 26th day of November, 1903, May 19, 20, and 21, 1904. With this limitation to a vegetable diet and with regular methods of living, the nitrogenous waste material was found to be constant within very narrow limits. Emphasis, however, should be laid upon the fact that there was no prescription of diet, but perfect freedom of choice, although this choice was limited wholly to vegetable and cereal foods.

The accompanying tables give the output of nitrogen, uric acid, etc., through the kidneys for various dates between May[110] 14, 1903, and June 15, 1904. Scrutiny of these tables shows that the average daily output of nitrogen, so far as the data show, amounted to 8.58 grams. This indicates an average daily metabolism of 53.62 grams of proteid material.

Likewise noticeable is the perfectly steady body-weight throughout this whole period of time, while the low level of 8.5 grams of metabolized nitrogen testifies to an economy in the use of proteid food, which indicates that in this subject at least the needs of the body for proteid food could easily be met by an amount equal to about one-half that called for by the Voit and similar standard dietaries.

[111]

BEERS.

Date. Body-weight. Urine.
Volume. 24 hours. Sp. Gr. Nitrogen. Uric Acid. P₂O₅.
1904 kilos c.c. grams gram grams
May 14 61.1 940 1020 8.23 0.330 1.82
Oct. 8 920 1014 6.40 0.374 1.47
13 61.1 740 1026 8.74 0.375 1.61
14 780 1024 8.37
15 970 1018 8.90 0.374 1.04
16 1365 1014 9.09
17 1295 1013 8.86
18 1400 1013 7.56 0.347 1.57
20 61.1 1304 1014 8.14 0.328 1.44
21 1510 1012 7.97
22 1450 1012 8.26 0.338 1.95
23 1130 1013 7.86
24 1060 1019 8.46
25 1275 1015 8.25 0.375 1.74
26 1390 1014 7.34
27 61.4 1000 1020 7.50 0.344 1.38
Nov. 21 61.4 670 1025 8.72
22 925 1017 8.21 0.335 1.28
23 585 1027 8.36
24 885 1023 8.02 0.354
25 800 1026 7.92
26 1095 1020 10.77* 0.364 1.53
Jan. 5 61.4 1110 1018 8.99 0.324
7 650 1024 8.15 0.278 1.29
8 710 1020 7.88
9 910 1023 8.73
10 890 1020 8.01 0.327 1.21
11 875 1017 7.51
12 480 1029 6.77
13 580 1023 8.00 0.398
14 765 1022 8.35
15 1360 1017 9.22
16 61.4 990 1020 8.79
17 835 1024 8.47 0.354
18 780 1020 8.05
19 790 1022 8.10 0.382
Feb. 9 860 1023 8.46 0.355
[112] 10 61.4 850 1024 8.57 0.226
11 61.4 750 1022 8.55 0.352
12 61.4 595 1026 8.46 0.368
13 61.4 640 1027 8.75 0.425
14 60.8 730 1025 8.28 0.353
Apr. 18 61.5 610 1025 7.69 0.365
daily
average
19 61.5 870 1020 9.87
20 61.5 985 1019 8.87
21 61.5 795 1024 8.25
22 61.5 1090 1019 9.02
23 61.5 970 1022 8.44
24 61.5 810 1021 7.30
25 61.5 850 1018 6.94 0.691
26 61.5 620 1024 7.11
28 450 1027 8.58
29 650 1025 9.52
30 1260 1018 10.20
May 1 1060 1017 8.71
2 610 1025 8.16
3 650 1022 8.70
4 61.5 870 1019 8.51
5 61.3 610 1025 8.31
6 61.3 655 1026 8.72 0.356
7 680 1025 8.53
8 60.8 490 1026 7.00
9 61.3 550 1026 7.59
10 705 1025 7.78
11 730 1025 8.28
12 800 1025 9.36
16 715 1022 7.29
17 990 1018 6.95
18 715 1026 7.81
19 845 1926 10.45
20 61.5 1170 1020 11.02
21 61.2 795 1025 10.02
22 835 1020 8.42
23 695 1025 9.42
24 660 1025 9.82
[113] 25 700 1025 9.91 0.434
26 620 1026 8.59
27 665 1026 9.53
28 61.2 960 1021 10.31
29 790 1023 9.24
31 930 1025 10.44
June 1 855 1018 8.76
2 850 1023 8.01
3 860 1020 9.24
4 61.4 1145 1021 10.17
5 590 1024 7.47
6 510 1029 7.53
7 620 1027 8.26
8 985 1020 8.45
9 1220 1020 8.49
10 1220 1017 8.28
11 1710 1013 8.82
12 925 1017 7.11
13 920 1020 8.01
14 1090 1015 8.64
15 61.5 915 1022 8.68
Daily average 880 1021 8.58 0.365 1.49

* Turkey eaten on this day.

On these three days, meat, fish, and eggs were eaten.

On February 9, a nitrogen balance was attempted covering a period of six days, in which there was an exact comparison of the nitrogen income and output. In this balance period it will be observed that the total amount of nitrogen taken in for the six days was 53.108 grams, while the output of nitrogen through the kidneys amounted to 51.07 grams. The nitrogen excreted through the fæces, however, brought the total nitrogen output up to 58.83 grams, thus making a minus balance for the six days of 5.722 grams of nitrogen. During this period the average fuel value of the food per day was 2168 calories. The average daily output of metabolized[114] nitrogen during the period was 8.5 grams, practically identical with the average daily excretion of nitrogen through the kidneys for the entire year, so far as determined. We have here a distinct minus balance, due either to an insufficient amount of proteid food, or an insufficient fuel value.

Tuesday, February 9, 1904.

Breakfast.—Oatmeal 237.5 grams, butter 10 grams, sugar 35 grams, milk 60 grams, coffee 210 grams.

Lunch.—Macaroni 142 grams, cheese 10.5 grams, bread 71.5 grams, sweet potato 119.5 grams, milk 250 grams.

Dinner.—Bread 80.7 grams, butter 20 grams, mashed potato 176 grams, string beans 77.5 grams, apple pie 82 grams, milk 250 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Oatmeal 237.5 × 0.64 = 1.520 grams.
Butter 10 + 20 = 30.0 × 0.088 = 0.026
Sugar 35.0 × 0.00 = 0.000
Milk 60 + 250 + 250 = 560.0 × 0.52 = 2.912
Coffee 210.0 × 0.10 = 0.210
Macaroni 142.0 × 0.87 = 1.235
Cheese 10.5 × 4.45 = 0.467
Bread 71.5 + 80.7 = 152.2 × 1.36 = 2.069
Sweet potato 119.5 × 0.28 = 0.334
Mashed potato 176.0 × 0.36 = 0.633
String beans 77.5 × 0.26 = 0.201
Apple pie 82.0 × 0.49 = 0.401
Total nitrogen in food 10.008 grams.
Total nitrogen in urine 8.460
Fuel value of the food 2094 calories.

[115]

Wednesday, February 10, 1904.

Breakfast.—Oatmeal 299 grams, butter 19 grams, cream 71 grams, sugar 41 grams, coffee 210 grams.

Lunch.—Bread 79 grams, butter 11 grams, boiled potato 155.2 grams, milk 250 grams.

Dinner.—Bread 56 grams, butter 12 grams, baked beans 100 grams, cranberry sauce 150 grams, sugar 21 grams, coffee 210 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Oatmeal 99.0 × 0.60 = 1.794 grams.
Butter 19 + 11 + 12 = 42.0 × 0.088 = 0.036
Cream 71.0 × 0.47 = 0.333
Sugar 41 + 21 = 62.0 × 0.00 = 0.000
Coffee (breakfast) 210.0 × 0.12 = 0.252
Bread 79 + 56 = 135.0 × 1.65 = 2.227
Boiled potato 155.2 × 0.39 = 0.605
Milk 250.0 × 0.55 = 1.375
Baked beans 100.0 × 1.40 = 1.400
Cranberry sauce 150.0 × 0.04 = 0.060
Coffee (dinner) 210.0 × 0.11 = 0.231
Total nitrogen in food 8.313 grams.
Total nitrogen in urine 8.570
Fuel value of the food 1723 calories.

Thursday, February 11, 1904.

Breakfast.—Oatmeal 300 grams, cream 71 grams, butter 10 grams, sugar 41 grams, coffee 210 grams.

Lunch.—Butter 14 grams, bread 126 grams, boiled sweet potato 205 grams, milk 250 grams.

Dinner.—Bread 22 grams, butter 7.5 grams, mashed potato 100 grams, sugar 14 grams, milk 250 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Oatmeal 300.0 × 0.40 = 1.200 grams.
Cream 71.0 × 0.49 = 0.347
Butter 10 + 14 + 7.5 = 31.5 × 0.088 = 0.027
[116]Sugar 41 + 14 = 55.0 × 0.00 = 0.000
Coffee 210.0 × 0.096 = 0.201
Bread 126 + 22 = 148.0 × 1.75 = 2.590
Sweet potato 205.0 × 0.31 = 0.635
Milk 250 + 250 = 500.0 × 0.51 = 2.550
Mashed potato 100.0 × 0.36 = 0.360
Total nitrogen in food 7.910 grams.
Total nitrogen in urine 8.550
Fuel value of the food 1979 calories.

Friday, February 12, 1904.

Breakfast.—Oatmeal 300 grams, butter 10 grams, cream 74 grams, sugar 41 grams, coffee 210 grams.

Lunch.—Bread 86 grams, butter 9 grams, potato 200 grams, sugar 14 grams, milk 250 grams.

Dinner.—Bread 63 grams, butter 14 grams, mashed potato 150 grams, apple dumpling 136 grams, milk 250 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Oatmeal 300 × 0.52 = 1.560 grams.
Butter 10 + 9 + 14 = 33 × 0.088 = 0.029
Cream 74 × 0.50 = 0.370
Sugar 41 + 14 = 55 × 0.00 = 0.000
Coffee 210 × 0.11 = 0.231
Bread 86 + 63 = 149 × 1.71 = 2.547
Potato 200 × 0.41 = 0.820
Milk 250 + 250 = 500 × 0.48 = 2.400
Mashed potato 150 × 0.37 = 0.555
Apple dumpling 136 × 0.72 = 0.979
Total nitrogen in food 9.491 grams.
Total nitrogen in urine 8.460
Fuel value of the food 2209 calories.

[117]

Saturday, February 13, 1904.

Breakfast.—Oatmeal 300 grams, butter 12 grams, cream 70 grams, sugar 41 grams, coffee 210 grams.

Lunch.—Bread 80 grams, butter 11 grams, sweet potato 132 grams, sugar 20 grams, milk 250 grams.

Dinner.—Bread 59.5 grams, mashed potato 175 grams, butter 11 grams, sugar 20 grams, apple pie 141 grams, milk 250 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Oatmeal 300.0 × 0.43 = 1.290 grams.
Butter 12 + 11 + 11 = 34.0 × 0.088 = 0.029
Cream 70.0 × 0.50 = 0.350
Sugar 41 + 20 + 20 = 81.0 × 0.00 = 0.000
Coffee 210.0 × 0.11 = 0.231
Bread 80 + 59.5 = 139.5 × 1.64 = 2.287
Sweet potato 132.0 × 0.37 = 0.488
Milk 250 + 250 = 500.0 × 0.54 = 2.700
Mashed potato 175.0 × 0.37 = 0.647
Apple pie 141.0 × 0.43 = 0.606
Total nitrogen in food 8.628 grams.
Total nitrogen in urine 8.750
Fuel value of the food 2395 calories.

[118]

Sunday, February 14, 1904.

Breakfast.—Oatmeal 300 grams, butter 16 grams, cream 70 grams, sugar 41 grams, coffee 210 grams.

Lunch.—Baked potato 171 grams, bread 72 grams, butter 15 grams, sugar 21 grams, apple sauce 38 grams, milk 250 grams.

Dinner.—Bread 35.5 grams, butter 13.5 grams, mashed potato 180 grams, sugar 20 grams, chocolate cake 111 grams, ice cream 115 grams, milk 250 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Oatmeal 300.0 × 0.46 = 1.380 grams.
Butter 16 + 15 + 13.5 = 44.5 × 0.088 = 0.039
Cream 70.0 × 0.50 = 0.350
Sugar 41 + 21 + 20 = 82.0 × 0.00 = 0.000
Coffee 210.0 × 0.11 = 0.231
Baked potato 171.0 × 0.41 = 0.701
Bread 72 + 35.5 = 107.5 × 1.75 = 1.881
Apple sauce 38.0 × 0.029 = 0.011
Milk 250 + 250 = 500.0 × 0.40 = 2.000
Mashed potato 180.0 × 0.37 = 0.666
Chocolate cake 111.0 × 0.75 = 0.832
Ice cream 115.0 × 0.58 = 0.667
Total nitrogen in food 8.758 grams.
Total nitrogen in urine 8.280
Fuel value of the food 2610 calories.

[119]

NITROGEN BALANCE.—Beers.

Nitrogen
Taken in.
Output.
Nitrogen in Urine. Weight of Fæces (dry).
Feb. 9 10.008 grams. 8.46 grams.
10 8.313 8.57 44.7 grams.
11 7.910 8.55 19.0
12 9.491 8.46 30.0
13 8.628 8.75 28.0
14 8.758 8.28 5.0
126.7 grams contain
6.13% N.
53.108 51.07 + 7.76 grams nitrogen.
53.108 grams nitrogen. 58.83 grams nitrogen.
Nitrogen balance for six days = -5.722 grams.
Nitrogen balance per day = -0.953 gram.

Average Intake.

Calories per day 2168.
Nitrogen per day 8.85 grams.

[120]

On May 6, a second nitrogen balance was attempted covering a period of seven days, in which, as before, there was an exact comparison of the income and output of nitrogen. In this period of seven days, as shown in the accompanying tables, the fuel value of the food was essentially the same as in the preceding period, but the amount of proteid food was increased to an average intake of 10.10 grams per day. Under these conditions there was a distinct plus balance for the seven days amounting to 2.425 grams, thus showing that with this quantity of nitrogenous food the body was laying on nitrogen to the extent of 0.346 gram per day. The average daily amount of nitrogen metabolized during this period was only 8.18 grams, being quite noticeably below the average daily amount for the year. In other words, the results of this balance period show that with a consumption of food sufficient to yield about 2200 calories per day, the body of this subject needed to metabolize only 8.25 grams of nitrogen per day to more than maintain nitrogen equilibrium. Following are the tables of results:

[121]

Friday, May 6, 1904.

Breakfast.—Oatmeal 345 grams, butter 7 grams, sugar 30 grams, milk 100 grams, coffee 180 grams.

Dinner.—Bread 67 grams, potato 71 grams, corn 179 grams, pie 133 grams, milk 200 grams.

Supper.—Biscuit 75 grams, butter 11 grams, potato 106 grams, cake 52 grams, apricots 75 grams, milk 230 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Oatmeal 345 × 0.40 = 1.380 grams.
Butter 7 + 11 = 18 × 0.11 = 0.020
Sugar 30 × 0.00 = 0.000
Milk 100 + 200 + 230 = 530 × 0.54 = 2.862
Coffee 180 × 0.14 = 0.252
Bread 67 × 1.39 = 0.931
Potato (dinner) 71 × 0.52 = 0.369
Corn 179 × 0.44 = 0.788
Pie 133 × 0.54 = 0.718
Biscuit 75 × 1.21 = 0.908
Potato (supper) 106 × 0.36 = 0.382
Cake 52 × 0.90 = 0.468
Apricots 75 × 0.21 = 0.158
Total nitrogen in food 9.236 grams.
Total nitrogen in urine 8.720
Fuel value of the food 2080 calories.

Saturday, May 7, 1904.

Breakfast.—Oatmeal 382 grams, milk 100 grams, coffee 185 grams, butter 10 grams, sugar 30 grams.

Dinner.—Bread 93 grams, potato 67 grams, rice pudding 141 grams, milk 200 grams.

Supper.—Bread 67 grams, butter 13 grams, potato salad 122 grams, milk 240 grams, coffee 120 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Oatmeal 382 × 0.41 = 1.566 grams.
Milk 100 + 200 + 240 = 540 × 0.54 = 2.916
Coffee (breakfast) 185 × 0.13 = 0.241
[122]Butter 10 + 13 = 23 × 0.11 = 0.025
Sugar 30 × 0.00 = 0.000
Bread 93 + 67 = 160 × 1.33 = 2.128
Potato 67 × 0.56 = 0.375
Rice pudding 141 × 0.76 = 1.072
Potato salad 122 × 0.35 = 0.427
Coffee (supper) 120 × 0.15 = 0.180
Total nitrogen in food 8.930 grams.
Total nitrogen in urine 8.530
Fuel value of the food 1714 calories.

Sunday, May 8, 1904.

Breakfast.—Oatmeal 386 grams, butter 10 grams, sugar 35 grams, milk 100 grams, coffee 185 grams.

Dinner.—Rice and chicken gravy 178 grams, boiled onions 136 grams, chocolate pudding 141 grams, milk 150 grams.

Supper.—Potato salad 73 grams, bread 28 grams, chocolate cake 104 grams, milk 220 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Oatmeal 386 × 0.35 = 1.351 grams.
Butter 10 × 0.11 = 0.011
Sugar 35 × 0.00 = 0.000
Milk 100 + 150 + 220 = 470 × 0.55 = 2.585
Coffee 185 × 0.11 = 0.204
Rice and chicken gravy 178 × 0.47 = 0.837
Onions 136 × 0.25 = 0.340
Chocolate pudding 141 × 1.03 = 1.452
Potato salad 73 × 0.35 = 0.256
Bread 28 × 1.33 = 0.372
Chocolate cake 104 × 0.95 = 0.988
Total nitrogen in food 8.396 grams.
Total nitrogen in urine 7.000
Fuel value of the food 1995 calories.

[123]

Monday, May 9, 1904.

Breakfast.—Oatmeal 330 grams, butter 10 grams, sugar 35 grams, milk 100 grams, coffee 185 grams.

Dinner.—Bread 73 grams, fried potato 125 grams, boiled onions 118 grams, macaroni and cheese 128 grams, apple pie 110 grams, milk 200 grams.

Supper.—Bread 82 grams, boiled potato 130 grams, butter 12 grams, chocolate cake 114 grams, milk 245 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Oatmeal 330 × 0.44 = 1.452 grams.
Butter 12 + 10 = 22 × 0.11 = 0.024
Sugar 35 × 0.00 = 0.000
Milk 100 + 200 + 245 = 545 × 0.58 = 3.161
Coffee 185 × 0.099 = 0.183
Bread 73 + 82 = 155 × 1.33 = 2.062
Fried potato 125 × 0.48 = 0.600
Onions 118 × 0.25 = 0.295
Macaroni and cheese 128 × 1.53 = 1.958
Apple pie 110 × 0.55 = 0.605
Boiled potato 130 × 0.30 = 0.390
Chocolate cake 114 × 0.95 = 1.083
Total nitrogen in food 11.813 grams.
Total nitrogen in urine 7.590
Fuel value of the food 2620 calories.

Tuesday, May 10, 1904.

Breakfast.—Oatmeal 357 grams, butter 11 grams, sugar 35 grams, milk 100 grams, coffee 185 grams.

Dinner.—Soda biscuit 68 grams, boiled potato 160 grams, butter 20 grams, stewed tomato 103 grams, custard pie 103 grams, milk 200 grams.

Supper.—Soda biscuit 81 grams, butter 14 grams, stewed potato 97 grams, chocolate cake 66 grams, milk 200 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Oatmeal 357 × 0.42 = 1.499 grams.
Butter 11 + 20 + 14 = 45 × 0.11 = 0.050
Sugar 35 × 0.00 = 0.000
[124]Milk 100 + 200 + 200 = 500 × 0.54 = 2.700
Coffee 185 × 0.13 = 0.241
Soda biscuit 68 + 81 = 149 × 1.27 = 1.892
Boiled potato 160 × 0.30 = 0.480
Stewed tomato 103 × 0.21 = 0.216
Custard pie 103 × 0.91 = 0.937
Stewed potato 97 × 0.45 = 0.437
Chocolate cake 66 × 0.95 = 0.627
Total nitrogen in food 9.079 grams.
Total nitrogen in urine 7.780
Fuel value of the food 2190 calories.

Wednesday, May 11, 1904.

Breakfast.—Oatmeal 394 grams, butter 10 grams, sugar 35 grams, milk 100 grams, coffee 185 grams.

Dinner.—Soup 141 grams, bread 78 grams, butter 14 grams, boiled potato 101 grams, corn 128 grams, rice pudding 116 grams, milk 200 grams.

Supper.—Biscuit 103 grams, butter 11 grams, corn 113 grams, cake 60 grams, milk 205 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Oatmeal 394 × 0.46 = 1.812 grams.
Butter 10 + 14 + 11 = 35 × 0.11 = 0.039
Sugar 35 × 0.00 = 0.000
Milk 100 + 200 + 205 = 505 × 0.54 = 2.727
Coffee 185 × 0.13 = 0.241
Soup 141 × 0.48 = 0.677
Bread 78 × 1.25 = 0.975
Boiled potato 101 × 0.31 = 0.313
Corn 113 + 128 = 241 × 0.46 = 1.109
Rice pudding 116 × 0.63 = 0.731
Biscuit 103 × 1.42 = 1.463
Cake 60 × 0.78 = 0.468
Total nitrogen in food 10.555 grams.
Total nitrogen in urine 8.280
Fuel value of the food 2183 calories.

[125]

Thursday, May 12, 1904.

Breakfast.—Oatmeal 349 grams, butter 10 grams, sugar 35 grams, milk 100 grams, coffee 185 grams.

Dinner.—Soup 137 grams, fried potato 43 grams, bread 100 grams, macaroni and cheese 122 grams, bread pudding 80 grams, milk 200 grams.

Supper.—Stewed potato 126 grams, bread 122 grams, cake 73 grams, apricots 81 grams, milk 220 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Oatmeal 349 × 0.41 = 1.431 grams.
Butter 10 × 0.11 = 0.011
Sugar 35 × 0.00 = 0.000
Milk 100 + 200 + 220 = 520 × 0.57 = 2.964
Coffee 185 × 0.13 = 0.241
Soup 137 × 0.48 = 0.658
Fried potato 43 × 0.76 = 0.327
Bread 100 + 122 = 222 × 1.25 = 2.775
Macaroni and cheese 122 × 1.94 = 2.370
Bread pudding 80 × 0.82 = 0.656
Stewed potato 126 × 0.43 = 0.542
Cake 73 × 0.78 = 0.569
Apricots 81 × 0.23 = 0.186
Total nitrogen in food 12.730 grams.
Total nitrogen in urine 9.360
Fuel value of the food 2283 calories.

[126]

NITROGEN BALANCE.—Beers.

Nitrogen
Taken in.
Output.
Nitrogen in Urine. Weight of Fæces (dry).
May 6 9.236 grams. 8.72 grams. 17.5 grams.
7 8.930 8.53 30.5
8 8.396 7.00 26.2
9 11.813 7.59 27.1
10 9.079 7.78 22.1
11 10.555 8.28 26.0
12 12.730 9.36 24.5
12.5
186.4 grams contain
5.93% N.
70.739 57.26 + 11.054 grams nitrogen.
70.739 grams nitrogen. 68.314 grams nitrogen.
Nitrogen balance for seven days = +2.425 grams.
Nitrogen balance per day = +0.346 gram.

Average Intake.

Calories per day 2152.
Nitrogen per day 10.10 grams.

[127]

Here we have, as in the preceding cases, marked physiological economy of non-nitrogenous as well as of nitrogenous food material. Further, taking the body-weight of the subject as 61.5 kilos, and with an average daily excretion of 8.58 grams of metabolized nitrogen, it is evident that under the existing conditions of life and activity there was need for the metabolism of only 0.139 gram of nitrogen per kilo of body-weight. Doubtless, however, still greater economy was possible.

Finally, while it hardly savors of scientific accuracy to quote simple sensations, yet it may be stated that the subject asserts a betterment of his condition, with continuance of mental and physical vigor in such a degree that he has persisted now for more than a year and a half in the maintenance of these dietetic habits which are characterized by this lowered rate of proteid metabolism. The quantity of nitrogen metabolized daily means the breaking down of approximately 50 grams of proteid, and it is very evident that this amount of proteid food, one-half the amount called for by the ordinary diet, is quite sufficient to meet all of the subject’s bodily needs, even with a total fuel value considerably below 2500 calories.

Summary

Certain general conclusions seem to be justified by the results reported. A healthy man, whose occupation is such as not to involve excessive muscular work, but whose activity is mainly mental rather than physical, though by no means excluding the latter, can live on a much smaller amount of proteid or albuminous food than is usually considered essential for life, without loss of mental or physical strength and vigor, and with maintenance of body and nitrogen equilibrium. This means that the ordinary professional man who leads an active and even strenuous life, with its burden of care and responsibility, need not clog his system and inhibit his power for work by the ingestion of any such quantities of proteid food as the ordinary dietetic standards call for.[128] There is no real physiological need—that is apparent—for the adoption of such dietetic habits as ordinarily prevail, or as are called for by the dietary standards set by most authorities in this branch of physiology. There is no justifiable ground for the dictum, or the assumption, that the adult man of average body-weight needs daily 118 grams of proteid food for the maintenance of health, strength and vigor, or that there is need for the metabolism of at least 16 grams of nitrogen daily. If such were the case, how could these five subjects, whose experiences have been detailed in the foregoing pages, have maintained their body-weight, established nitrogen equilibrium, pursued their ordinary vocations without loss of strength and vigor, and kept in a perpetual condition of good health, with an average daily metabolism of from 5.4 grams of nitrogen to 8.99 grams of nitrogen for periods ranging from six to eighteen months? Surely, if 16 to 18 grams of nitrogen are a daily requisite for the healthy adult, there should have been some sign of nitrogen starvation during these long periods of low proteid diet, but the sharpest scrutiny failed to find it. On the contrary, there were not wanting signs of improved conditions of the body which could not well be associated with anything but the changes in diet.

Let us briefly consider the main facts. The writer, of 57 kilos body-weight, showed for nearly nine consecutive months an average daily metabolism of 5.7 grams of nitrogen. During the last two months the daily metabolism averaged 5.4 grams of nitrogen. As body-weight and nitrogen equilibrium were both maintained under these conditions, it is certainly fair to assume that the physiological needs of the body were fully met. These figures imply a metabolism, in the first instance, of 0.1 gram of nitrogen per kilo of body-weight, while the lower figure shows a metabolism of 0.094 gram of nitrogen per kilo of body-weight. We may call this latter amount the minimal nitrogen requirement for this particular individual, under which health, strength, and vigor can be fully maintained. This lower nitrogen figure shows[129] that the needs of this particular individual for proteid material are met by the metabolism of 33.75 grams of proteid per day. Hence, one-third the usually accepted standard of proteid is quite sufficient for the wants of this particular person, and this too with a quantity of non-nitrogenous food far below the daily amount called for by ordinary physiological rules. A fuel value of 2000 calories per day was fully adequate to meet the ordinary wants of the body.

Dr. Mendel, with a body-weight of 70 kilos, showed for seven consecutive months an average daily metabolism of 6.53 grams of nitrogen, likewise with maintenance of health, strength, body equilibrium, and nitrogenous equilibrium. This figure implies a nitrogen metabolism of 0.093 gram per kilo of body-weight and shows that the wants of the body—in his case—can be fully met by a metabolism of 40.8 grams of proteid matter daily, and this likewise without increasing the amount of non-nitrogenous food ingested. Indeed, a total fuel value of 2500 calories per day was quite sufficient for all the needs of his body under the existing conditions.

Dr. Underhill, with a body-weight of 65 kilos, showed for six consecutive months a proteid metabolism equal to 7.81 grams of nitrogen per day, while for the last two months the daily average excretion of nitrogen was only 6.68 grams. These figures mean respectively a nitrogen metabolism of 0.120 and 0.102 gram of nitrogen per kilo of body-weight. Here, too, as in the preceding cases, this lowered rate of proteid metabolism was maintained without increasing the total fuel value of the food and with a continuance of health and strength.

Messrs. Dean and Beers, with body-weights of 64 and 61.5 kilos respectively, likewise kept up their health and strength for a long period of time with a nitrogen metabolism averaging 8.99 and 8.58 grams of nitrogen per day, i. e., with a metabolism of 0.140 and 0.139 gram of nitrogen per kilo of body-weight respectively, and this with a total fuel value in their daily food averaging not more than 2500 calories.

[130]

With this general concurrence of results, we are certainly warranted in the assertion that the professional man can safely practise a physiological economy in the use of proteid food equal to a saving of one-half to two-thirds the amount called for by existing dietary standards, and this without increasing the amount of non-nitrogenous food consumed. Indeed, the latter class of foods can likewise be diminished in amount without detriment to health or strength, where there is no call for great physical exertion. Lastly, the so-called minimal proteid requirement of the healthy man—which for this group of individuals we may place at the low level of 0.093 to 0.130 gram of nitrogen per kilo of body-weight—represents the real physiological needs of the system for nitrogen, and in so far as our present data show, anything beyond this quantity may be considered as an excess over and above what is required for the actual physiological necessities of the body. Naturally, however, there may be nothing detrimental in a slight excess of proteid beyond the daily needs. That is a subject, however, to be discussed later in connection with other results.

In view of the close agreement in the amount of nitrogen metabolized by these different individuals per kilo of body-weight, emphasis should be laid upon the fact that the results recorded were all obtained with perfect freedom of choice in the matter of diet, without prescription of any kind, so that the close concurrence in the final figures tends to strengthen the value of the data as pointing to a certain minimal requirement easily attainable, and fully adequate for meeting the needs of the body.


[131]

II. EXPERIMENTS WITH VOLUNTEERS FROM THE HOSPITAL CORPS OF THE UNITED STATES ARMY.

The original Detachment from the Hospital Corps of the United States Army detailed to serve in this series of experiments arrived in New Haven September 28, 1903, under the command of Dr. Wallace DeWitt, 1st Lieutenant and assistant Surgeon of the United States Army. The detail was composed of twenty men, of whom fourteen were privates, volunteers for the experiment, the remainder being made up of non-commissioned officers, cook, cook’s helper, etc. The detachment was located in a convenient house on Vanderbilt Square belonging to the Sheffield Scientific School, and there they lived during their six months’ stay in New Haven under military discipline, and subject to the constant surveillance of the commanding officer and the non-commissioned officers.

In selecting the men for the experiment particular attention was paid to securing as great a variety of types as possible, representing different nationalities, temperaments, etc. Naturally, among such a group of enlisted men brought together for the purpose in view many were found unsuited for various reasons, and were quickly exchanged for others better adapted for the successful carrying out of the experiment. Several quickly deserted, apparently not relishing the restrictions under which they were compelled to live. The restriction which constituted the greatest hardship in the eyes of several of the men was the regularity of life insisted upon, and the consequent restraint placed upon their movements in the city when relieved from duty. The following Statement from Dr. DeWitt will explain the causes of removal of the men who dropped out of the experiment during the natural sifting process of the first few weeks and later.

[132]

Hospital Corps Detachment U. S. Army,
332 Temple St., New Haven, Conn.,
March 17, 1904.

Professor Russell H. Chittenden,
Director Sheffield Scientific School,
New Haven, Conn.

Sir,—In compliance with your verbal request concerning men of this detachment lost by transfer and desertion and the reasons therefor, I have the honor to inform you that the following men were lost by transfer, at my request, for the reasons set after their respective names:

Private Edward Mcdermott (October 17, 1903). Mentally and morally unsuited.

Private Paul Forkel (October 18, 1903). Physically unsuited.

Private David Acker (October 24, 1903). Physically unsuited by reason of Acute Pulmonary Tuberculosis Bilateral.

Private William C. Witzig (November 17, 1903). Physically unsuited by reason of Cardiac Irritability.

Private Philip S. Myer (December 11, 1903). Physically unsuited by reason of very high grade of Myopia both eyes.

Private first class Charles P. Davis (January 14, 1904). Physically unsuited by reason of Acute Melancholia.

Private Barnard Bates (February 12, 1904). Morally and mentally unsuited by reason of Drunkenness.

In all these men, except Private Davis, the condition for which they were transferred was present when they reported for duty with the detachment.

In the case of Private Davis, his condition of acute melancholia in my opinion was incident to the experiment,—due to the necessary restrictions of liberty and food, assisted by a natural gloomy disposition.

The following men were lost by desertion:

Private first class Samuel R. Curtis (November 3, 1903).

Private first class William Smith (November 5, 1903).

Private Simon Prins (January 23, 1904).

Private Edwin A. Rinard (February 3, 1904).

[133]

Of these men Private first class Smith and Private Prins were on duty in the kitchen and were at no time subject to restriction of diet and liberty. Private first class Curtis deserted before the experiment was well under way and can not be attributed to any cause arising out of the investigation. Private Rinard’s desertion was in my opinion due to the restrictions of diet and liberty incident to the experiment. I would say, however, that this man was a worthless character and was discharged “without honor” from the army during a previous enlistment.

Very respectfully,

(Signed) Wallace Dewitt,
1st Lieut. and Asst. Surgeon U. S. Army,
Commdg. Detachment.

As supplementing Dr. DeWitt’s statement it may be mentioned that Rinard reported for the experiment at New Haven on December 11, 1903, and remained here until February 2, 1904. On December 11 he weighed 59.8 kilos, while on February 2, the last day he was here, his body-weight was 60 kilos. Evidently, any restriction of diet he may have suffered had not made any great impression upon his bodily condition.

There were thirteen men of the detachment who really took part in the experiment, and of these all but four were in the original detail. Of these four, two joined in October and two early in November. Of these thirteen, all but two continued to the close of the experiment, April 4, 1904.

The following statement gives the name, age, birthplace, occupation, length of service (U. S. Army), etc. of the thirteen men.

It will be noted that the men range in age from twenty-one years six months to forty-three years, and that representatives of many countries are on the list.

Regarding the duties of the men, i. e., their daily work, the following statement from Dr. DeWitt will give all needed information on this point. The character of the Gymnasium work will be referred to later.

[134]

Name. Age on
Oct. 1, 1903
(Years and
Months).
Length of
Service on
Oct. 1, 1903.
(Years and
Months).
Birthplace. Occupation before
Original Enlistment.
Remarks.
Private first class.
Broyles, Jonah 24-6 3-3 Campbell Co., Tenn. Scholar Joined Nov. 13, 1903.
Coffman, William E. 22-1 0-2 Edinsburg, W. Va. Clerk Joined Sept. 28, 1903.
Fritz, Charles J. 27-8 3-0 Switzerland. Gasfitter Joined Oct. 30, 1903.
Henderson, James D. 25-1 2-0 Marshall, N. C. Student Joined Sept. 28, 1903.
Loewenthal, Maurice D. 22-8 0-2 New York, N. Y. Clerk Joined Sept. 28, 1903.
Morris, William 21-6 3-8 San Juan, P. R. Scholar Joined Sept. 28, 1903.
Oakman, William H. 43-0 1-7 Blackville, S. C. Bookkeeper Joined Sept. 28, 1903.
Sliney, William F. 26-7 5-0 Roxbury, Mass. Painter Joined Oct. 21, 1903.
Steltz, John J. B. 23-1 0-3 Schuylkill, Pa. Painter Joined Sept. 28, 1903.
Zooman, Ben 25-3 1-11 London, Eng. Hosp. Orderly Joined Sept. 28, 1903.
Private.
Cohn, Isaac 21-8 0-1 Jerusalem, Pal. Porter in Drug store Joined Nov. 13, 1903.
Transferred.
Private first class.
Davis, Charles P. 27-0 0-2 Darlington Co. S. C. Machinist Joined Sept. 28, 1903; left Jan. 14, 1904.
Private.
Bates, Barnard 26-8 1-10 San Francisco, Cal. Painter Joined Sept. 28, 1903; left Feb. 12, 1904.

[135]

Hospital Corps Detachment U. S. Army,
332 Temple Street, New Haven, Conn.
,
March 17, 1904.

Professor R. H. Chittenden,
Director Sheffield Scientific School,
New Haven, Conn.

Sir,—In compliance with your verbal request I have the honor to inform you that the duties of this detachment during the tour of duty at this station have been as follows:—

At 6.45 A. M. the men arise and their body-weights are taken immediately, after which they dress and assemble for reveille roll-call.

7.15. Breakfast. After this meal they are all engaged in various duties about the quarters, such as inside and outside police, kitchen police, assisting in measurement of urine and fæces and transportation of the same to the laboratory; cleansing of fæces cans and urine bottles, etc. They are occupied with these various duties until about 9 A. M.

9 A. M. Detachment proceeds to Gymnasium under charge of a non-commissioned officer, and by him reported to the gymnastic instructor.

11 A. M. Detachment returns from Gymnasium.

12 M. Dinner.

1 P. M. Drill, weather permitting, otherwise a walk in charge of a non-commissioned officer, or indoor instruction relative to the duties of a soldier.

2 P. M. Relief from drill; walk, or instruction.

2.30 P. M. Instruction by a non-commissioned officer in their duties as nurses, etc.

3.30 P. M. Relief from instruction.

5 P. M. Supper.

5.30 P. M. Retreat roll-call.

10 P. M. All men in bed.

This routine is the same for every day in the week except Saturday and Sunday. On Saturday drill and instruction in the afternoon are omitted, and on Sundays the men are also free from gymnasium work.

In addition to the duties mentioned above, a special detail of two men is made every morning to assist in the weighing and serving[136] of the food, and from time to time details are sent to the laboratory and reported to Dr. Mendel for such work connected with the investigation as he might assign them.

Very respectfully,

(Signed) Wallace DeWitt,
1st Lieut. and Asst. Surgeon U. S. Army,
Commdg. Det. H. C.

Here we have a group of men, thirteen in number, quite different in type from the preceding group; men accustomed to living a vigorous life under varying conditions, and who naturally had great liking for the pleasures of eating. Further, they were men who had no personal interest whatever in the experiment or in the principles involved. To be sure, they had volunteered for the work, and the objects of the experiment had been fully explained to them. Like good soldiers they no doubt desired to obey orders, and they doubtless preferred to see the experiment a success rather than a failure, but they had not that interest that would lead them to undergo any great personal discomfort. This point should be kept in mind, since it has a distinct bearing upon the possibility of establishing physiological economy of diet in persons who would not willingly incommode themselves or suffer personal inconvenience.

The experiment commenced on October 4, 1903, and for a period of six months every detail bearing upon the nutrition and condition of the men under the gradually changed conditions was carefully observed. Every precaution to preserve the health and good spirits of the men was taken. Pure distilled water was sent to the quarters each morning, magazines and other periodicals were supplied through the courtesy of friends, occasional visits to the theatre were indulged in; in fact all that could be done to counterbalance any possible depressing influence from the partial restraints of the experiment was arranged for.

Showing a group of the soldiers at work in the gymnasium.

Regarding the details of the work; the twenty-four hours’ urine was collected by each man, also the fæces for each day, and these were subjected to chemical analysis with a view to[137] following out the various changes in the amount and character of the proteid metabolism going on in the body as measured by the output of total nitrogen, uric acid, and phosphoric acid in the urine, and by the amount of nitrogen in the fæces with reference to the degree of digestion and utilization of the proteid foods ingested.

During the first two weeks the ordinary army rations were given to the men; later a gradual change was made, accompanied by a reduction in the amount of proteid food, with some reduction likewise in the total fuel value of the food. All the food placed before each man was carefully weighed, and at the close of every meal any uneaten food was weighed and the amount subtracted from the initial weights. During the balance periods, when the income and output of nitrogen were carefully compared, the food materials were weighed with greater care and large samples of each article were taken for analysis, to determine the exact content of nitrogen. Every figure for nitrogen shown in the tables was verified by at least a duplicate chemical analysis so as to avoid any possibility of error.

It is not necessary to give here any detailed description of the changes made in the character of the diet, since on pages 288 to 326 may be found the daily dietary from October 2, 1903, to April 4, 1904,—each meal of the day,—showing the amount and character of the food given the men during the six months period. It should be stated, however, that at no time were the men placed on a cereal diet or on a truly vegetable diet. The object in view was simply to study the possibilities of a general physiological economy in diet, with special reference to the minimal proteid requirement of the healthy man. To be sure, in doing this meats, owing to their high content of proteid, were very much reduced in amount and on many days no meat at all was given, but as the dietary is looked through it will be seen that the main change was from a heavy meat diet (rich in proteid) to a lighter diet, comparatively poor in proteid, with an increasing predominance of vegetable and cereal foods. Condiments are also[138] noticeable in the diet, together with the ordinary accessories, coffee and tea. Variety was also considered as a necessary factor, not to be overlooked, as contributing largely to the maintenance of a proper physiological condition.

From a study of the tables which follow, showing the chemical composition of the daily urine, it will be seen that during the first sixteen days, viz., from October 4 until October 20 or 21, when the men were on the ordinary army ration with opportunity to eat an abundance of meat, the daily urine frequently contained 16 to 17 grams of nitrogen, showing a metabolism of over 100 grams of proteid on such days. Sliney, indeed, averaged for four days an output of 18.19 grams of nitrogen, while Coffman, Henderson, and Zooman showed an average daily excretion of about 15 grams of nitrogen each for the sixteen days from October 4.

[139]

OAKMAN.

Date. Body-weight. Urine.
Volume. 24 hours. Sp. Gr. Nitrogen. Uric Acid. P₂O₅.
1903 kilos c.c. grams gram grams
Oct. 4 66.7 1160 1019 16.37 0.549 2.76
5 66.7 1030 1025 12.36
6 66.0 740 1029 11.85 0.703 1.15
7 66.0 480 1031 10.31
8 65.4 660 1030 14.30 0.574 1.32
9 65.4 830 1029 15.94
10 65.4 1440 1018 17.02
11 66.1 2220 1012 16.12 0.591 2.64
12 66.7 1300 1020 13.33
13 66.8 2140 1013 15.67 0.610 2.56
14 66.4 1290 1017 12.38
15 66.7 1730 1017 14.95 0.653 1.93
16 66.7 1520 1017 13.68
17 66.2 1490 1018 15.20
18 66.2 2030 1014 16.44 0.646 2.66
19 65.8 1580 1017 16.78
20 65.3 1900 1014 16.19 0.626 1.95
21 65.4 1100 1024 12.07
22 66.0 1200 1018 11.30 0.502 1.11
23 66.4 2060 1015 11.37
24 67.2 1970 1015 11.88
25 67.1 1480 1014 8.64 0.411 2.07
26 67.2 1510 1018 11.78
27 67.2 1890 1015 12.13 0.406 1.99
28 67.4 1620 1014 9.82
29 67.6 980 1018 6.82 0.493 1.62
30 67.5 820 1022 10.91
31 67.0 930
Nov. 1 67.4 1480 1015 10.20 0.460 1.49
2 67.6 1160 1018 10.37
3 67.4 1160 1020 10.44 0.489 1.53
4 67.1 720 1024 6.61
5 66.6 640 1029 8.02 0.495 1.17
6 66.5 1200 1016 9.57
7 66.0 840 1023 8.57
8 66.0 1100 1017 8.32 0.452 1.67
9 66.0 720 1030 8.53
10 66.4 880 1022 10.19 0.515 1.30
11 66.6 1080 1018 9.72
12 66.9 920 1023 8.38 0.616 1.54
[140] 13 67.2 800 1025 6.43
14 66.5 600 1026 7.38
15 66.3 1360 1014 8.98 0.403 1.44
16 66.4 1160 1025 9.88
17 66.4 900 1020 6.69 0.343 0.94
18 66.0 1820 1010 7.92 0.436 daily av. 1.09 daily av.
19 65.4 1160 1017 5.57
20 66.0 1120 1020 8.73
21 66.4 1020 1020 7.89
22 66.1 1360 1016 8.16 0.413 1.83
23 67.0 2600 1008 8.11
24 65.9 1140 1015 6.43 0.380 1.90
25 65.9 1800 1011 7.56
26 65.6 1200 1020 7.63 0.377 1.71
27 66.2 1300 1015 7.41
28 65.9 1200 1012 6.70
29 65.9 1480 1019 8.79 0.531 1.73
30 65.4 1540 1011 8.41
Dec. 1 65.0 1080 1015 7.13 0.484 1.45
2 65.6 1440 1012 8.38
3 64.5 940 1021 8.58 0.438 1.66
4 65.0 780 1022 7.22
5 65.4 1280 1016 8.06
6 65.4 1880 1012 7.67 0.320 1.86
7 65.0 1600 1013 6.24
8 64.9 1680 1011 7.86 0.304 1.77
9 65.0 1180 1013 7.74
10 64.7 1120 1016 7.59 0.308 1.37
11 64.7 860 1021 7.58
12 64.8 700 1026 6.34
13 64.6 880 1022 7.87 0.404 1.47
14 64.7 1540 1017 9.33
15 64.2 1140 1015 6.98 0.436 1.71
16 64.3 1040 1018 6.74
17 64.4 980 1018 6.94 0.368 1.05
18 64.7 1605 1015 8.57
19 64.2 1250 1013 8.77
20 63.4 1000 1016 7.56 0.462 1.25
21 63.6 1190 1016 8.35
22 63.0 1470 1011 8.47 0.245 1.26
[141] 23 63.6 672 1028 5.88
24 63.8 980 1017 6.55 0.294 0.89
25 63.5 2310 1008 6.37
26 63.9 1860 1016 6.92
27 63.5 1590 1015 7.54 0.380 1.11
28 63.0 1840 1018 8.39
29 62.9 1145 1018 6.11 0.546 0.72
30 63.2 1300 1020 6.78
31 63.5 1080 1020 5.96 0.421 1.18
1904
Jan. 1 64.0 2360 1013 8.64 0.329 1.43
2 63.6 1270 1018 5.33
3 64.0 2475 1012 7.42
4 63.6 1820 1012 5.63
5 63.0 1520 1013 6.66
6 63.5 1270 1016 6.71
7 63.0 1135 1016 6.74 0.344 1.06
8 63.5 870 1022 6.06
9 63.6 1640 1010 6.89
10 63.6 1240 1015 5.95 0.409 1.42
11 63.5 1740 1012 7.31
12 63.0 840 1020 6.00 0.439
13 62.9 885 1021 7.33 0.490
14 63.0 1425 1015 8.29 0.441
15 62.8 1000 1023 7.14 0.390
16 62.9 1525 1015 8.23 0.372
17 62.7 1740 1017 8.14 0.400
18 62.3 1200 1020 8.42 0.423 1.32
19 62.7 990 1023 7.60
20 62.7 985 1020 7.51
21 62.7 1080 1021 8.23
22 62.7 1670 1010 7.01
23 62.2 970 1017 6.58
24 62.2 1800 1013 7.99
25 62.2 1630 1013 7.43 0.412 1.45
26 62.0 880 1026 6.86
27 62.5 1250 1017 9.07
28 62.4 1560 1016 8.61
29 62.7 1325 1018 6.28
30 62.9 2015 1013 7.25
[142] 31 62.4 1730 1018 6.64
Feb. 1 62.8 910 1027 5.51 0.395 1.42
2 63.0 1610 1016 7.15
3 62.5 1330 1020 7.18
4 62.7 1480 1023 7.46
5 63.0 1600 1020 6.62
6 63.2 1980 1012 6.53
7 63.0 1775 1015 6.39
8 62.3 1860 1013 8.26 0.233
9 62.9 2010 1013 7.36
10 62.0 1195 1025 7.60
11 62.9 1580 1016 8.82
12 62.5 1900 1013 8.09
13 62.4 1560 1016 7.30
14 62.5 1480 1017 7.90
15 62.5 1610 1023 8.93 0.430
16 63.0 1570 1019 7.86
17 62.8 2375 1014 9.69
18 62.2 1060 1022 7.80
19 62.0 910 1029 8.13
20 62.3 1710 1012 8.10
21 62.6 1940 1010 7.33
22 62.4 1250 1021 7.73 0.489
23 62.7 1700 1012 6.53
24 62.4 1525 1017 8.65
25 62.2 1980 1013 8.55
26 62.0 1145 1017 6.77
27 61.8 1150 1019 6.87
28 62.0 1445 1020 7.46
29 62.2 1015 1024 6.88
Mar. 1 62.6 1225 1019 7.42
2 62.5 1620 1017 7.58
3 62.3 1585 1016 6.85
4 62.3 1815 1015 7.95
5 62.0 1565 1014 6.10
6 62.0 1700 1020 7.96
7 62.0 1240 1016 7.44 0.411
8 62.5 1710 1015 8.72
9 62.0 1670 1016 7.71
10 62.5 1590 1016 7.63
[143] 11 62.0 1410 1021 8.71
12 62.1 1530 1018 7.44
13 62.1 1780 1016 8.65
14 62.0 1300 1019 8.11 0.468
15 62.0 1820 1012 7.29
16 62.2 1670 1017 9.12
17 62.4 1380 1020 8.20
18 62.7 1785 1015 7.82
19 62.5 1910 1017 7.68
20 62.7 1965 1013 6.72
21 62.1 930 1026 5.72 0.429
22 62.4 1770 1012 7.86
23 62.0 1560 1017 7.21
24 62.0 1860 1015 8.15
25 61.6 1130 1023 7.19
26 62.0 2000 1013 8.88
27 61.9 1320 1019 7.13
28 62.0 1025 1025 6.64 0.379
29 62.4 1830 1018 8.34
30 62.3 1500 1020 6.30
31 62.0 1600 1021 7.10
Apr. 1 62.0 2070 1014 6.83
2 62.0 1250 1025 5.55
3 62.0 2115 1009 4.57
4 62.1 2110 1013 5.95
Daily average from Oct. 21 1437 1017 7.42 0.405 1.39

[144]

MORRIS.

Date. Body-weight. Urine.
Volume. 24 hours. Sp. Gr. Nitrogen. Uric Acid. P₂O₅.
1903 kilos c.c. grams gram grams
Oct. 4 59.2 970 1023 13.74 0.563 1.46
5 59.2 1340 1018 13.43
6 58.4 720 1026 9.16 0.546 1.42
7 58.9 685 1028 12.70
8 58.4 400 1019 5.27 0.179 0.54
9 58.4 820 1027
10 58.4 1260 1023 13.68
11 58.5 1400 1020 18.48 0.782 2.32
12 58.5 1220 1021 13.40
13 58.6 1580 1016 13.84 0.614 2.21
14 58.3 1070 1027 16.05
15 58.9 850 1029 13.82 0.626 1.50
16 58.9 940 1020 15.40
17 59.2 1500 1015 11.70
18 59.0 1150 1026 15.73 0.796 2.19
19 58.5 1160 1028 18.86
20 58.4 1160 1026 14.62
daily
average
0.602
daily
average
1.77
daily
average
21 58.4 1050 1030
22 58.6 910 1027
23 58.6 1100 1024
24 58.8 1030 1029
25 59.0 1080 1023
26 59.1 1060 1028 10.30 0.638 1.37
27 58.1 1240 1021
28 59.1 860 1025
29 60.0 800 1026
30 59.7 880 1022
31 59.6 640
Nov. 1 60.0 990 1020
2 59.6 750 1028 7.60 0.437 1.26
3 59.9 900 1027
4 60.0 980 1018
5 59.0 1180 1018
6 59.5 320 1026
7 58.7 620 1029
8 58.8 1220 1013
9 58.6 860 1023 7.03 0.413 1.02
10 59.4 800 1024
11 59.0 860 1020
12 59.1 760 1025
[145] 13 59.2 740 1027
14 59.1 1160 1014
15 59.0 560 1027
16 58.6 860 1026 5.88 0.345 0.84
17 58.7 680 1020
18 58.6 580 1022
19 58.4 920 1016
20 59.0 880 1027
21 59.5 840 1019
22 59.0 680 1029
23 59.3 1040 1015 7.34 0.477 1.12
24 59.5 1260 1020
25 59.3 820 1020
26 59.3 740 1032
27 60.0 1020 1016
28 59.4 860 1023
29 59.4 700 1028
30 59.5 880 1020 9.55 0.607 1.63
Dec. 1 59.1 1020 1019
2 59.8 1420 1021
3 59.2 1240 1027
4 59.5 720 1031
5 59.6 800 1022
6 59.6 820 1028
7 59.4 840 1029 7.73 0.410 1.48
8 59.6 540 1020
9 59.4 880 1026
10 59.7 900 1018
11 59.2 780 1025
12 59.1 740 1028
13 59.1 820 1022
14 59.0 840 1028 6.68 0.332 1.24
15 58.9 1020 1018
16 58.9 810 1025
17 59.0 1020 1019
18 58.6 720 1026
19 58.5 785 1023
20 58.2 670 1020
21 58.2 810 1031 6.97 0.375
22 58.5 680 1026
[146] 23 58.6 785 1024
24 58.6 930 1020
25 58.8 1040 1017
26 57.6 945 1020
27 58.6 840 1023
28 58.8 1070 1020 6.70 0.296 1.20
29 58.4 1205 1018
30 59.0 1000 1026
31 59.0 935 1027
1904
Jan. 1 58.5 1475 1016
2 58.6 1350 1018
3 58.6 545 1028
4 58.7 840 1022 6.41 0.332 1.11
5 58.6 1040 1020
6 58.8 680 1024
7 59.0 1040 1020
8 58.4
9 58.4 1110 1019
10 58.6 1120 1016
11 58.9 1010 1017 5.58
12 58.8 685 1019 4.19 0.405
13 58.5 800 1029 7.92 0.785
14 58.0 785 1027 7.91 0.494
15 58.0 800 1030 7.44 0.488
16 58.0 1195 1018 7.38 0.421
17 58.0 880 1020 5.28 0.304
18 58.0 1080 1026 7.31 0.449 1.40
19 58.0 1075 1019
20 58.0 920 1019
21 57.9 715 1031
22 58.0 820 1022
23 58.0 1065 1024
24 58.2 1370 1014
25 58.1 1490 1015 7.18 0.369 1.33
26 58.2 1300 1025
27 58.2 1335 1019
28 58.3 1110 1014
29 58.4 915 1028
30 58.4 1200 1020
[147] 31 58.4 1490 1020
Feb. 1 58.4 870 1030 7.04 0.418 1.36
2 58.9 680 1024
3 58.9 1150 1029
4 58.9 1900 1025
5 59.0 930 1030
6 59.1 1030 1021
7 59.0 975 1024
8 59.5 880 1030 7.69 0.484
9 59.4 970 1027
10 59.0 1020 1025
11 59.0 1015 1021
12 58.9 930 1028
13 59.3 880 1029
14 59.2 1150 1018
15 59.2 1050 1028 7.49 0.423
16 59.0 1310 1027
17 59.4 1300 1017
18 59.1 1400 1020
19 58.9 930 1030
20 58.7 715 1030
21 58.7 1240 1023
22 59.3 915 1025 6.30 0.471
23 59.4 1520 1017
24 58.8 940 1027
25 59.0 1405 1022
26 59.4 940 1022
27 59.1 1375 1021
28 59.1 810 1025
29 59.0 1100 1026 6.40 0.394
Mar. 1 59.1 1035 1026 6.64
2 58.8 990 1025 5.40
3 59.0 1235 1022 6.55
4 58.9 1075 1025 4.99
5 59.0 1280 1016 5.38
6 58.8 1230 1026 7.01
7 58.3 1100 1029 7.05 0.723
8 58.8 1200 1021
9 59.0 1310 1021
10 59.0 1280 1020
[148] 11 58.8 1310 1026
12 59.0 1350 1022
13 59.1 1110 1025
14 58.8 855 1027 7.37 0.493
15 58.9 965 1026
16 58.8 1210 1026
17 58.8 1410 1022
18 59.0 1500 1020
19 59.0 1290 1026
20 59.0 1040 1024
21 59.0 1040 1024 6.67 0.552
22 58.9 980 1028
23 58.8 880 1030
24 59.0 950 1027
25 59.3 1210 1028
26 59.2 1210 1024
27 59.2 1210 1022
28 59.1 1280 1026 6.68 0.446
29 59.0 1065 1027 5.69
30 59.0 1030 1028 6.06
31 59.0 1400 1025 6.96
Apr. 1 58.8 1940 1019 7.10
2 59.0 1480 1025 6.13
3 59.0 1470 1017 4.67
Daily average from Oct. 20 1017 1023 7.03 0.450 1.25

[149]

BROYLES.

Date. Body-weight. Urine.
Volume. 24 hours. Sp. Gr. Nitrogen. Uric Acid. P₂O₅.
1903 kilos c.c. grams gram grams
Nov. 15 59.4 2500 1008 7.35
16 59.0 2600 1006
17 59.3 2600 1009 7.95
daily
average
0.381
daily
average
1.93
daily
average
18 58.7 2400
19 58.0 1280 1014
20 58.7 1800 1013
21 58.5 2240 1008
22 59.0 2100 1011
23 58.0 1500 1009 6.98 0.326 1.36
24 57.7 1700 1011
25 58.0 1080 1014
26 57.8 1620 1016
27 58.0 700 1026
28 58.0 2100 1007
29 58.0 1240 1015
30 58.0 1880 1010 7.40 0.333 1.68
Dec. 1 57.5 1760 1010
2 57.4 1700 1009
3 57.4 1680 1011
4 57.0 1280 1013
5 57.0 1420 1017
6 57.6 2600 1009
7 57.6 600 1021 7.39 0.265 1.68
8 57.5 1960 1012 10.09
9 57.5 2060 1010 8.53
10 57.2 2280 1010 8.89
11 56.4 800 1021 6.67
12 56.8 660 1030 6.77
13 56.5 920 1021 8.00
14 56.6 1620 1013 7.48 0.319 1.28
15 56.4 1100 1015
16 56.4 1090 1017
17 56.2 990 1019
18 56.2 590 1026
19 56.0 750 1027
20 56.1 630 1022
21 56.1 1560 1012 6.41 0.289 0.91
22 56.0 1050 1014
23 56.5 680 1023
24 56.4 960 1020
[150] 25 56.6 1235 1017
26 56.5 950 1020
27 56.9 1520 1012
28 56.0 1265 1019 6.70 0.297 1.17
29 55.8 1560 1018
30 55.6 1710 1009
31 56.3 1135 1016
1904
Jan. 1 56.0 1110 1016
2 56.7 1470 1014
3 56.9
4 57.2 1790 1010 5.99 0.371 1.27
5 58.0 1100 1013
6 57.1 640 1028
7 56.6 1180 1004
8 57.0 1190 1016
9 57.6 810 1025
10 56.8 1590 1010
11 57.0 1820 1011 6.99
12 55.7 525 1027 5.38 0.621
13 55.9 530 1031 6.99 0.595
14 55.5 530 1032 7.47 0.514
15 55.0 1300 1077 9.67 0.428
16 56.0 1355 1016 7.65 0.386
17 55.6 800 1020 5.28 0.291
18 55.4 1770 1016 7.80 0.364 1.29
19 55.0 2080 1010
20 55.6 1285 1017
21 55.6 1570 1013
22 56.0 2630 1007
23 55.7 1330 1015
24 56.9 1470 1015
25 57.0 2140 1009 6.81 0.369 1.43
26 57.2 1670 1013
27 58.4 2140 1015
28 58.0 1030 1018
29 58.0 1080 1010
30 58.6 1080 1021
31 58.8 1670 1015
Feb. 1 58.4 770 1029 7.06 0.409 1.54
[151] 2 58.5 1020 1020
3 59.0 1800 1020
4 58.6 1390 1025
5 59.0 1240 1025
6 59.6 1280 1019
7 59.0 990 1025
8 58.3 1485 1017 7.91 0.438
9 59.4 1900 1013
10 59.0 1530 1025
11 59.0 1000 1023
12 58.6 790 1031
13 58.7 1030 1025
14 58.9 1260 1015
15 59.0 1000 1028 7.55 0.376
16 59.2 2110 1012
17 59.3 1805 1017
18 59.1 735 1026
19 59.0 1260 1020
20 59.0 1040 1020
21 59.0 1775 1012
22 59.3 1290 1019 6.18 0.423
23 59.5 2010 1011
24 59.7 650 1027
25 59.4 2300 1011
26 60.5 1145 1019
27 60.0 855 1025
28 60.3 670 1031
29 60.5 1310 1017 5.74 0.306
Mar. 1 60.3 1235 1022 9.26
2 60.1 1550 1014 6.97
3 60.2 1470 1014 6.18
4 60.0 1580 1015 7.68
5 60.5 2060 1008 5.56
6 60.0 1755 1013 7.69
7 60.0 1230 1016 9.99 0.428
8 60.2 950 1030
9 60.5 1330 1017
10 61.0 1620 1016
11 60.5 1160 1029
12 61.0 1350 1025
[152] 13 61.6 1670 1015
14 62.0 1540 1017 8.19 0.484
15 61.4 1160 1021
16 61.4 1445 1016
17 61.4 1610 1019
18 61.5 1220 1018
19 61.0 1145 1025
20 61.3 1155 1017
21 61.2 1230 1021 7.07 0.580
22 61.3 1350 1018
23 61.2 1180 1019
24 61.4 1490 1016
25 61.3 1620 1018
26 61.4 1040 1023
27 61.0 1160 1021
28 61.0 1640 1015 6.79 0.359
29 61.0 1400 1020 7.06
30 61.0 2055 1014 7.27
31 61.0 1190 1023 6.21
Apr. 1 61.2 1320 1018 5.86
2 61.0 1005 1028 5.61
3 61.0 2025 1013 7.17
Daily average from Nov. 15 1396 1017 7.26 0.398 1.41

[153]

COFFMAN.

Date. Body-weight. Urine.
Volume. 24 hours. Sp. Gr. Nitrogen. Uric Acid. P₂O₅.
1903 kilos c.c. grams gram grams
Oct. 4 59.1 2140 1012 17.33 0.373 2.03
5 59.1 1780 1015 15.27
6 58.7 1070 1024 12.62 0.641 2.05
7 58.6 1800 1016 16.96
8 58.6 1120 1024 14.49 0.480 1.89
9 58.4 1150 1024 10.14
10 58.3 2180 1012 16.06
11 59.1 1580 1014 13.55 0.474 1.75
12 59.1 980 1025 12.99
13 59.0 1820 1014 14.85 0.613 2.50
14 59.2 1150 1025 13.94
15 58.9 2120 1013 16.03 0.337 2.23
16 59.0 1220 1019 14.41
17 59.0 1680 1019 12.60
18 59.6 2720 1011 13.87 0.453 1.86
19 59.4 2360 1017 23.64 3.01
20 58.3 1320 1019 13.21
daily
average
0.475
daily
average
1.76
daily
average
21 59.1 1030 1024
22 59.2 650 1029
23 59.6 1640 1017
24 59.8 1320 1022
25 60.0 2300 1013
26 59.8 1440 1022 11.40 0.524 1.91
27 59.8 1280 1020
28 60.2 1200 1017
29 60.2 1000 1017
30 59.6 820 1030
Nov. 1 59.7 1020 1020
2 59.4 700 1031 8.71 0.430 1.61
3 60.0 880 1025
4 59.6 560 1031
5 59.3 540 1032
6 59.1 440 1036
7 58.6 460 1035
8 58.4 420 1035
9 58.6 700 1030 8.61 0.431 1.12
10 59.0 620 1030
11 58.5 600 1029
12 58.7 840 1028
13 58.7 600 1032
[154] 14 58.7 600 1033
15 58.9 920 1021
16 58.7 720 1030 8.41 0.395 1.30
17 58.4 720 1031
18 59.3 720 1027
19 58.7 980 1026
20 59.0 1400 1022
21 59.2 600 1029
22 58.7 800 1031
23 59.0 640 1026 8.72 0.439 1.49
24 59.5 1120 1022
25 59.6 1280 1017
26 59.0 820 1028
27 59.0 740 1030
28 59.0 360 1031
29 59.2 1060 1029
30 59.2 760 1032 11.14 0.586 1.52
Dec. 1 58.9 1140 1027
2 59.5 780 1026
3 58.5 800 1030
4 59.5 860 1030
5 59.5 920 1030
6 59.5 760 1032
7 59.4 860 1030 9.95 0.400 1.62
8 59.4 540 1030
9 59.0 660 1034
10 59.0 640 1033
11 58.3 580 1034
12 59.1 800 1032
13 58.5 680 1030
14 57.3 560 1032 7.79 0.372 1.25
15 58.3 680 1025
16 58.5 910 1021
17 58.4 700 1024
18 58.4 1110 1018
19 57.8 600 1030
20 57.3 550 1032
21 58.0 600 1031 7.31 0.288
22 57.7 470 1037
23 58.0 645 1031
[155] 24 58.3 900 1014
25 57.8 730 1028
26 58.0 1085 1014
27 58.0 1000 1021
28 57.6 1035 1016 7.60 0.246 1.20
29 57.2 1145 1015
30 57.4 1002 1023
31 57.4 1300 1016
1904
Jan. 1 57.6 1240 1020
2 56.4 950 1018
3 57.0 1038 1021
4 57.6 1325 1008 7.16 0.271 1.28
5 58.2 1640 1014
6 58.6 1090 1017
7 58.0 1090 1015
8 57.4 785 1026
9 57.7 710 1028
10 57.4 1080 1014
11 57.0 600 1027 8.14
12 57.0 930 1020 8.82 0.508
13 56.9 580 1031 8.28 0.508
14 56.7 1040 1018 8.30 0.312
15 56.5 650 1033 7.91 0.352
16 56.5 1130 1017 7.32 0.305
17 56.5 800 1025 7.44 0.315
18 56.4 1540 1012 6.95 0.301 1.11
19 56.4 1510 1016
20 56.5 1220 1016
21 56.2 505 1033
22 56.3 900 1019
23 56.4 1325 1013
24 56.2 510 1030
25 56.6 1460 1012 7.55 0.340 1.09
26 56.7 1400 1015
27 56.7 1520 1018
28 57.0 1720 1013
29 56.5 520 1035
30 56.5 870 1028
31 56.7 980 1024
[156]Feb. 1 56.2 700 1032 7.56 0.362 1.24
2 56.9 1310 1020
3 57.2 1120 1024
4 57.3 1260 1028
5 58.0 1970 1018
6 57.0 810 1022
7 56.8 780 1030
8 56.6 1130 1021 8.65 0.420
9 57.0 1300 1020
10 56.8 1140 1025
11 57.4 1340 1020
12 57.2 1360 1023
13 57.0 1020 1025
14 57.0 1720 1014
15 56.5 890 1032 8.18 0.318
16 57.2 1190 1025
17 57.4 1250 1019
18 57.0 1630 1015
19 56.7 1225 1025
20 57.0 900 1025
21 57.0 1590 1016
22 57.0 985 1028 7.62 0.395
23 57.0 1465 1013
24 56.7 1160 1020
25 56.5 1340 1016
26 56.3 1015 1017
27 56.0 630 1032
28 56.7 1205 1027
29 57.0 1530 1017 8.63 0.365
Mar. 1 57.0 1030 1022 7.48
2 56.8 1295 1020 8.62
3 56.7 1040 1022 7.18
4 56.0 1130 1023 7.93
5 56.5 1540 1014 7.67
6 56.6 1105 1024 7.95
7 56.3 1190 1018 8.27 0.338
8 56.5 1350 1017
9 56.2 880 1031
10 56.8 1500 1016
11 56.9 1120 1024
[157] 12 56.6 1600 1018
13 57.2 1230 1022
14 57.0 1150 1022 8.07 0.288
15 57.3 1580 1014
16 57.3 1290 1023
17 57.5 1355 1018
18 58.0 1635 1016
19 56.8 1320 1020
20 57.0 1085 1021
21 57.4 1030 1023 8.50 0.478
22 57.7 1970 1013
23 57.4 1670 1013
24 57.0 870 1031
25 57.0 1000 1024
26 57.3 1320 1023
27 58.0 1500 1018
28 58.1 1485 1019 8.37 0.371
29 58.0 1580 1021 8.06
30 57.8 1415 1019 6.88
31 57.8 1285 1026 7.78
Apr. 1 57.8 1135 1023 7.32
2 57.0 1415 1022 6.45
3 58.0 2000 1018 4.12
Daily average from Nov. 2 1034 1024 8.17 0.379 1.23

[158]

SLINEY.

Date. Body-weight. Urine.
Volume. 24 hours. Sp. Gr. Nitrogen. Uric Acid. P₂O₅.
1904 kilos c.c. grams gram grams
Oct. 21 61.3 1990 1021 22.68
23 61.2 1200 1025 16.77
24 61.2 1290 1027 17.58
25 61.4 1700 1016 15.72 0.686 2.59
27 62.4 1240 1024 11.10
daily
average
0.664
daily
average
1.26
daily
average
28 62.0 840 1025
29 62.2 630 1030
30 62.2 820 1029
31 62.0 960
Nov. 1 62.1 780 1030
2 61.7 940 1027 10.39 0.579 1.49
3 62.4 1020 1026
4 61.5 820 1028
5 61.7 650 1028
6 62.0 860 1022
7 61.5 780 1029
8 61.5 720 1026
9 61.7 1180 1020 9.71 0.625 1.39
10 62.0 620 1028
11 61.8 880 1027
12 61.8 1000 1027
13 61.6 920 1028
14 61.4 640 1031
15 61.0 920 1026
16 60.5 1000 1026 9.27 0.538 1.12
17 60.4 1080 1026
18 61.1 880 1029
19 60.9 940 1020
20 61.3 1020 1015
21 60.9 640 1032
22 60.4 800 1029
23 61.1 820 1021 8.66 0.650 1.07
24 60.6 700 1027
25 60.6 780 1023
26 60.8 780 1031
27 61.7 1240 1020
28 61.3 1080 1021
29 61.2 1000 1029
30 60.5 820 1029 10.12 0.677 1.88
Dec. 1 60.8 820 1026
[159] 2 60.0 600 1030
3 60.9 940 1015
4 60.9 1000 1024
5 59.9 1580 1016
6 61.0 840 1029
7 60.4 760 1028 8.40 0.671 1.66
8 60.4 920 1022 9.71
9 61.0 1000 1020 8.94
10 60.5 740 1025 8.66
11 59.9 760 1031 11.43
12 60.0 660 1033 9.78
13 59.9 880 1030 11.98
14 60.3 1120 1024 10.20 0.652 1.23
15 59.5 1060 1021
16 59.9 710 1030
17 59.9 880 1027
18 60.2 1200 1021
19 60.0 1125 1015
20 60.0 1210 1021
21 60.0 715 1026 8.97 0.606
22 59.5 940 1021
23 60.0 895 1023
24 59.9 1010 1018
25 59.8 1084 1026
26 61.0 940 1028
27 60.0 735 1023
28 59.8 1250 1019 7.20 0.515 1.29
29 59.7 1020 1020
30 60.0 1760 1016
31 60.0 980 1022
1904
Jan. 1 60.0 1370 1014
2 60.0 1152 1017
3 60.4 1035 1025
4 61.0 1210 1014 6.67 0.535 1.35
5 61.0 1090 1017
6 61.0 1400 1020
7 60.8 1140 1020
8 60.0
9 60.0 620 1028
[160] 10 60.6 1200 1020
11 61.8 1230 1015 7.23
12 61.3 560 1027 5.94 0.953
13 60.7 625 1029 8.44 0.988
14 60.7 600 1030 7.42 0.674
15 60.4 675 1032 7.89 0.693
16 60.5 500 1030 7.23 0.584
17 60.5 700 1030 8.15 0.691
18 60.3 500 1032 8.13 0.303 1.22
19 60.5 730 1026
20 60.6 920 1021
21 60.4
22 60.4 660 1017
23 60.0 920 1030
24 60.0 1320 1018
25 60.2 1220 1017 7.14 0.686 0.98
26 60.0 1260 1018
27 60.2 845 1024
28 60.3 560 1031
29 60.0 1030 1024
30 60.4 1330 1020
31 60.6 1125 1019
Feb. 1 60.7 830 1027 7.13 0.645 1.17
2 60.8 1695 1016
3 61.0 1760 1015
4 61.3 1060 1025
5 61.2 1300 1021
6 61.8 1880 1014
7 61.8 1260 1027
8 62.4 920 1021 7.66 0.647
9 62.5 1500 1022
10 62.6 1145 1026
11 62.3 710 1019
12 61.0 1350 1015
13 61.6 1030 1027
14 61.5 780 1029
15 61.5 1010 1030 8.07 0.600
16 61.7 1175 1025
17 62.1 1680 1017
18 62.0 1010 1024
[161] 19 61.6 770 1028
20 61.0 710 1030
21 61.0 1240 1021
22 61.2 1450 1017 8.86 0.746
23 61.6 1425 1017
24 62.0
26 62.4
27 61.4 1080 1019
28 61.4 835 1029
29 61.0 800 1030 9.50 0.697
Mar. 1 61.4 775 1028 8.09
2 61.0 760 1030 7.97
3 60.8 920 1023 7.78
4 61.0 960 1027 7.49
5 61.0 790 1029 7.54
6 61.0 980 1028 8.23
7 61.0
8 61.0 1480 1017 7.65 0.672
9 61.2 1960 1012
10 61.0 740 1028
11 60.8 950 1029
12 61.0 1370 1020
13 60.8 1310 1021
14 61.0 1460 1014 7.72 0.572
15 61.2 1155 1019
16 61.3 1100 1025
17 61.0 1465 1013
18 60.9 1300 1020
19 61.3 2270 1012
20 61.6 1040 1025
21 61.2 1020 1027 8.64 0.765
22 61.4 1210 1019
23 61.0 760 1029
24 60.5 900 1024
25 60.6 840 1029
26 60.8 890 1030
27 61.0 1000 1024
28 61.0 870 1026 7.09 0.502
29 61.0 825 1030 7.37
[162] 30 60.8 1080 1027 8.10
31 60.6 1030 1026 7.47
Apr. 1 60.6 1130 1021 6.78
2 60.0 1590 1016 6.20
3 60.6 1860 1013 6.59
Daily average from Nov. 1 1021 1024 8.39 0.647 1.32

[163]

STELTZ.

Date. Body-weight. Urine.
Volume. 24 hours. Sp. Gr. Nitrogen. Uric Acid. P₂O₅.
1903 kilos c.c. grams gram grams
Oct. 4 52.3 1860 1010 11.16 0.325 1.54
5 52.4 1020 1014 7.89
6 52.0 1120 1013 8.27 0.648 1.47
7 53.1 760 1014
8 52.0 1280 1012 9.93 0.549 1.70
9 52.0 1600 1014 8.83
10 52.6 1900 1012 14.59
11 52.6 1460 1010 7.97 0.368 1.55
12 52.6 1740 1013 10.07
13 52.9 2050 1013 12.79 0.758 2.00
14 52.9 1260 1013 8.77
15 52.6 1540 1013 12.20 0.512 1.60
16 52.8 1880 1014 14.41
17 52.5 1870 1013 14.36
18 52.4 2230 1013 15.12 0.561 2.53
19 52.5 1560 1010 8.89
20 52.4 1880 1013 11.61
daily
average
0.465
daily
average
2.01
daily
average
21 52.6 1060 1013
22 53.2 2100 1011
23 53.4 2320 1012
24 52.9 1460 1017
25 53.4 1660 1016
26 53.2 1150
27 53.4 1500 1016 8.65 0.493 1.44
28 53.2 1240 1011
29 53.6 1220 1015
30 53.3 1220 1015
31 52.9 1120
Nov. 1 53.0 1620 1016
2 53.8 1640 1014 6.81 0.364 1.32
3 53.5 1020 1011
4 52.6 1080 1014
5 53.2 1060 1015
6 53.0 1280 1014
7 53.1 1300 1014
8 52.9 760 1014
9 53.3 1060 1013 7.31 0.380 1.40
10 53.2 1340 1016
11 53.0 1140 1019
12 53.4 1360 1016
[164] 13 53.4 1300 1016
14 53.2 960 1017
15 53.3
16 53.2 1640 1016 8.07 0.409 1.45
17 53.4 1620 1015
18 53.4 1160 1017
19 52.9 1940 1015
20 53.4 1800 1014
21 53.4 1240 1015
22 53.0 1180 1020
23 53.4 1320 1013 6.71 0.390 1.35
24 53.4 2000 1013
25 53.5 1400 1016
26 53.7 780 1026
27 53.5 1000 1015
28 53.3 1600 1014
29 53.5 1340 1018
30 53.6 860 1020 7.49 0.394 1.50
Dec. 1 53.9 1960 1013
2 53.4 1060 1015
3 52.9 940 1018
4 53.6 1580 1019
5 53.6 980 1014
6 54.2 1280 1022
7 53.7 960 1021 7.01 0.420 1.46
8 53.4 620 1020 4.98
9 53.4 1000 1016 5.88
10 53.5 1420 1015 7.67
11 53.5 1360 1018 8.20
12 53.4 1040 1024 7.92
13 52.7 920 1022 5.57
14 53.0 1340 1024 10.21
15 52.9 1000 1019 7.98
16 52.9 940 1016 4.79 0.226 0.75
17 53.4 820 1015 9.04 0.452 1.48
18 53.4 1330 1016
19 53.4 1395 1014
20 53.1 1300 1017
21 53.2 1220 1016 7.42 0.387 0.80
22 53.1 1200 1018
[165] 23 53.2 1465 1017
24 53.1 1100 1021
25 53.2 970 1016
26 54.0 1350 1020
27 53.2 1105 1023
28 53.0 1240 1020 6.44 0.356 0.92
29 53.0 1180 1023
30 53.4 910 1018
31 53.4 810 1018
1904
Jan. 1 53.8 1220 1019
2 53.0 925 1024
3 53.6 870 1021
4 54.0 1055 1022 6.78 0.392 1.15
5 54.0 1050 1020
6 53.9 1195 1017
7 53.6 980 1021
8 53.4 1020 1021
9 53.3 1080 1022
10 53.6 1010 1021
11 53.9 960 1020 6.05
12 53.0 620 1021 4.61 0.487
13 53.6 1165 1019 7.90 0.609
14 52.9 645 1022 4.99 0.298
15 53.0 1450 1020 9.05 0.478
16 53.4 1300 1018 7.56 0.405
17 53.0 1440 1021 8.55 0.476
18 53.0 1440 1023 6.40 0.386 1.21
19 53.0 1115 1021
20 53.0 1180 1020
21 52.6 790 1024
22 52.7 660 1026
23 52.8 1750 1018
24 52.8 1440 1018
25 52.6 1200 1020 6.39 0.414 1.21
26 52.8 715 1023
27 52.7 1625 1015
28 52.8 1080 1016
29 52.8 1400 1020
30 53.0 1300 1021
[166] 31 53.4 1670 1019
Feb. 1 53.0 1800 1022 6.06 0.351 1.31
2 53.2 770 1018
3 53.3 1230 1022
4 53.4 1530 1018
5 53.2 1400 1023
6 53.0 1440 1021
7 53.4 1330 1018
8 53.0 1500 1022 7.71 0.523
9 53.0 940 1021
10 53.2 1400 1022
11 53.4 1620 1023
12 53.6 1645 1018
13 53.4 1370 1018
14 53.0 1200 1024
15 53.2 1560 1025 7.85 0.423
16 53.0 1540 1021
17 53.5 1610 1020
18 53.2 1280 1024
19 53.0 1560 1017
20 53.2 1635 1016
21 53.0 1110 1020
22 53.0 1860 1016 7.40 0.487
23 53.2 1470 1018
24 53.5 1205 1019
25 53.5 2140 1014
26 53.8 1080 1016
27 53.0 1165 1020
28 53.7 1360 1020
29 54.0 1400 1022 7.90
Mar. 1 53.9 1095 1021 5.98 0.389
2 53.4 1355 1020 6.58
3 53.2 2125 1015 8.09
4 53.0 1160 1016 4.66
5 53.2 1610 1022 8.69
6 53.0 1220 1022 8.20
7 53.0 720 1023 7.21 0.466
8 53.2 1160 1021
9 53.0 1280 1020
10 52.5 1210 1017
[167] 11 52.6 1770 1016
12 52.6 1510 1018
13 52.3 1110 1020
14 52.6 700 1023 7.22 0.414
15 52.7 1215 1018
16 53.0 1840 1013
17 52.6 1685 1014
18 52.4 1770 1015
19 53.2 1350 1012
20 52.6 910 1018
21 52.8 1210 1020 7.70 0.550
22 52.7 1680 1013
23 53.0 1630 1021
24 52.8 900 1020
25 52.6 1600 1018
26 53.0 1330 1019
27 52.8 1750 1020
28 53.0 845 1019 3.60 0.334
29 52.8 1490 1021 6.79
30 52.6 1790 1018 7.20
31 52.6 1560 1019 7.11
Apr. 1 52.4 1670 1021 7.82
2 52.6 1165 1013 3.28
3 53.0 1570 1018 6.50
Daily average from Nov. 2 1271 1018 7.13 0.416 1.24

[168]

HENDERSON.

Date. Body-weight. Urine.
Volume. 24 hours. Sp. Gr. Nitrogen. Uric Acid. P₂O₅.
1903 kilos c.c. grams gram grams
Oct. 4 71.3 1320 1020 17.50 0.635 1.97
5 71.3 1110 1019 9.79
6 71.8 1020 1028 12.67 0.515 1.93
7 71.6 1000 1017 12.00
8 71.2 840 1023 11.29 0.379 1.85
9 71.2 910 1030 14.20
10 71.5 2220 1013 16.78
11 71.7 1280 1022 16.28 0.587 2.04
12 72.2 1360 1021 15.59
13 72.4 910 1025 12.34 0.532 1.95
14 72.4 1400 1020 16.04
15 72.3 1700 1019 18.46 0.672 2.57
16 72.8 1740 1015 16.70
17 72.5 1620 1021 17.59
18 72.7 2260 1015 19.26 0.602 2.27
19 72.8 1150 1027 17.73
20 72.5 950 1030 14.31
daily
average
0.612
daily
average
1.60
daily
average
21 72.5 1060 1029
22 72.6 940 1017
23 72.4 1880 1017
24 72.8 1100 1029
25 72.6 920 1027
26 72.4 1120 1023 12.10 0.557 1.91
27 73.0 1930 1017
28 73.1 1340 1020
29 73.6 820 1026
30 73.4 960 1028
31 74.0 1040
Nov. 1 74.3 1540 1017
2 74.0 860 1031 9.90 0.518 1.71
3 74.0 1240 1024
4 74.0 840 1029
5 73.0 1280 1012
6 73.6 1340 1017
7 72.9 500 1032
8 72.5 920 1023
9 72.4 800 1029 9.98 0.563 1.60
10 72.4 600 1030
11 72.7 900 1022
12 72.8 780 1032
[169] 13 72.6 760 1032
14 72.0 960 1021
15 72.4 1460 1017
16 72.0 640 1031 9.33 0.478 1.31
17 72.0 820 1029
18 72.0 720 1030
19 72.0 880 1027
20 72.3 1200 1028
21 73.5 1200 1020
22 71.5 1180 1021
23 71.6 1040 1018 11.63 0.610 1.61
24 71.3 1040 1023
25 72.0 1020 1026
26 72.0 1200 1021
27 71.6 840 1030
28 72.0 720 1028
29 72.5 1400 1022
30 72.4 820 1023 10.69 0.536 1.58
Dec. 1 72.0 900 1027
2 72.1 1360 1017
3 71.4 980 1029
4 71.8 1160 1025
5 71.8 1740 1018
6 71.6 840 1028
7 71.0 880 1029 10.41
8 71.2 1100 1020 12.54
9 71.3 960 1021 11.92
10 71.4 1220 1019 12.21 0.428 1.74
11 71.2 680 1035 11.02
12 70.6 640 1036 9.60
13 70.6 940 1018 6.26
14 70.0 1280 1022 9.80 0.411 1.57
15 70.0 1260 1016
16 70.0 790 1028
17 70.2 980 1020
18 70.1 1060 1020
19 70.0 1510 1018
20 69.8 790 1023
21 69.5 650 1031 7.47 0.438
22 70.0 720 1023
[170] 23 70.0 450 1026
24 69.6 880 1024
25 69.5 1300 1019
26 69.0 930 1024
27 69.0 840 1024
28 69.0 920 1023 7.77 0.407 1.24
29 68.8 1180 1020
30 69.4 865 1024
31 70.0 1330 1026
1904
Jan. 1 68.9 890 1021
2 69.0 947 1027
3 69.1 1025 1030
4 69.2 890 1028 7.78 0.439 1.25
5 69.3 925 1027
6 69.3 550 1034
7 69.0 600 1029
8 68.8 880 1028
9 69.0 850 1027
10 69.0 1360 1015
11 68.9 610 1025 5.89
12 68.5 715 1024 7.68 0.498
13 68.6 835 1023 8.22 0.551
14 68.2 1040 1020 8.24 0.461
15 68.2 880 1025 7.76 0.440
16 68.2 970 1023 7.56 0.575
17 68.0 810 1023 7.87 0.441
18 68.0 1130 1020 7.82 0.445 1.18
19 68.0 1290 1018
20 68.2 670 1027
21 67.8 720 1030
22 67.5 520 1029
23 67.6 710 1030
24 67.6 775 1031
25 68.0 1220 1018 7.50 0.422 1.06
26 68.0 815 1016
27 68.3 920 1029
28 68.1 950 1023
29 68.2 670 1028
30 68.4 720 1030
31 68.4 1285 1020
[171]Feb. 1 68.0 790 1030 8.27 0.360 1.17
2 68.1 830 1031
3 68.5 1335 1024
4 68.5 1250 1026
5 69.0 1160 1031
6 69.0 1150 1022
7 68.5 1210 1024
8 68.0 935 1030 10.40 0.582
9 68.0 975 1030
10 68.2 990 1032
11 68.6 870 1032
12 69.0 1130 1027
13 69.4 1440 1019
14 69.0 715 1029
15 69.0 940 1029 11.80 0.510
16 68.0 1070 1027
17 68.1 1080 1027
18 68.0 945 1029
19 68.2 1010 1029
20 68.3 925 1029
21 69.0 1200 1020
22 68.6 1165 1024 7.53 0.640
23 68.2 1170 1022
24 68.6 1035 1027
25 68.4 1735 1016
26 69.0 775 1029
27 68.6 1090 1027
28 69.0 1020 1030
29 69.0 1935 1016 8.36 0.521
Mar. 1 68.7 840 1029 6.80
2 68.4 1160 1023 8.28
3 68.2 920 1026 7.37
4 68.0 1000 1029 8.22
5 68.0 1645 1018 8.09
6 68.0 1020 1030 8.20
7 68.0 740 1030 8.21 0.455
8 68.2 1470 1020
9 68.0 1660 1019
10 68.0 2040 1014
11 68.0 1030 1029
[172] 12 68.2 2450 1014
13 68.6 2300 1014
14 68.4 925 1026 8.82 0.483
15 68.4 1610 1016
16 68.5 1360 1019
17 68.0
18 68.6 1975 1016
19 69.0 2410 1015
20 69.3 2480 1011
21 68.6 850 1028 8.64 0.632
22 68.7 1800 1012
23 68.7 980 1023
24 69.0 1040 1030
25 69.2 1360 1022
26 69.2 2470 1013
27 69.3 2110 1015
28 69.4 1415 1020 8.40 0.337
29 69.4 1815 1019 9.04
30 69.4 1600 1017 5.95
31 69.0 1390 1018 5.42
Apr. 1 69.0 1930 1015 6.60
2 69.5 1405 1012 3.20
3 71.0 1330 1018 7.42
Daily average from Nov. 1 1102 1024 8.91 0.488 1.42

[173]

FRITZ.

Date. Body-weight. Urine.
Volume. 24 hours. Sp. Gr. Nitrogen. Uric Acid. P₂O₅.
1903 kilos c.c. grams gram grams
Nov. 1 76.0 1000 1024 11.34 1.14
2 76.4 950 1022 8.97
daily
average
0.418
daily
average
1.45
daily
average
3 77.8 2200 1017
4 76.0 960 1020
5 76.5 1420 1015
6 76.4 720 1018
7 75.8 940 1020
8 75.3 1580 1012
9 75.3 2240 1012 8.27 0.491 1.31
10 75.6 480 1021
11 76.0 1600 1015
12 76.2 1640 1013
13 76.2 880 1020
14 75.8 1320 1010
15 75.3 2000 1013
16 75.6 760 1017 8.13 0.528 1.54
17 75.6 1520 1013
18 76.0 1740 1013
19 75.1 1580 1015
20 76.0 1800 1015
21 75.7 1140 1017
22 75.7 1440 1013
23 76.0 2060 1011 8.68 0.555 1.63
24 76.2 2360 1011
25 75.6 2380 1011
26 75.8 2200 1013
27 77.2 1200 1014
28 75.5 920 1021
29 75.9 1240 1022
30 75.4 700 1026 8.16 0.656 1.74
Dec. 1 75.7 1480 1017
2 75.9 1160 1013
3 75.5 1480 1009
4 75.6 1860 1015
5 76.2 1480 1012
6 76.5 1460 1018
7 75.7 800 1024 5.81 0.746 1.97
8 75.6 880 1023 10.61
9 76.0
10 76.0 1840 1016 12.91
[174] 11 75.6 1240 1017 10.04
12 75.4 1740 1013 8.31
13 75.4 1400 1018 7.72
14 74.5 1260 1020 8.13 0.624 1.65
15 74.9 1040 1013
16 75.0 1390 1019
17 75.2 1220 1015
18 75.0 1520 1016
19 75.2 1380 1017
20 75.0 890 1020
21 74.8 1315 1018 7.42 0.584
22 74.8 880 1016
23 74.6 1135 1022
24 74.6 1596 1006
25 74.6 1300 1012
26 75.0 1090 1025
27 75.0 1520 1022
28 74.0 1150 1018 7.27 0.592 1.41
29 74.0 1250 1017
30 74.4 1610 1020
31 74.5 1025 1024
1904
Jan. 1 74.2 1620 1010
2 73.6 1990 1017
3 73.7 1036 1029
4 74.0 2070 1011 8.06 0.650 1.73
5 74.1 1320 1021
6 73.9 1690 1015
7 74.0
8 73.4 1940 1020
9 73.6 1560 1012
10 74.0 2200 1015
11 74.0 1300 1019 10.29
12 73.7 810 1023 8.99 1.100
13 74.0 680 1024 6.49 0.691
14 73.3 1230 1019 10.26 0.998
15 73.6 1030 1024 7.97 0.730
16 73.9 1045 1015 5.20 0.466
17 73.9 1910 1014 9.40 0.673
18 73.0 1060 1017 7.01 0.631 1.23
[175] 19 73.0 1510 1020
20 73.4 865 1023
21 73.4 1410 1020
22 73.0 610 1025
23 73.0 1630 1020
24 72.4 1125 1018
25 72.6 2400 1011 8.13 0.722 1.64
26 72.8 2100 1010
27 72.6 795 1018
28 73.0 1425 1019
29 73.0 1770 1013
30 73.2 1910 1015
31 73.0 2180 1016
Feb. 1 73.2 2075 1015 7.24 0.532 1.74
2 73.1 2280 1012
3 73.0 2360 1023
4 73.4 2200 1012
5 73.0 1600 1019
6 73.3 1745 1019
7 73.0 745 1023
8 73.5 2280 1012 9.02 0.699
9 73.2 2150 1015
10 73.1 1985 1018
11 73.4 2240 1010
12 73.0 2020 1016
13 73.6 1800 1016
14 73.0 1355 1021
15 73.0 1280 1024 8.43 0.632
16 73.5 2440 1014
17 73.4 1380 1022
18 73.6 1840 1020
19 73.6 2340 1016
20 73.6 2480 1010
21 73.4 850 1024
22 73.3 1985 1019 7.68 0.799
23 73.4 1535 1011
24 73.5 1940 1015
25 73.5 1520 1017
26 73.3 1030 1017
27 73.0 2270 1015
[176] 28 73.0 1660 1017
29 72.8 1165 1020 6.22 0.500
Mar. 1 73.2 1240 1020 7.44
2 73.2 915 1022 3.96
3 73.2 1740 1015 7.05
4 72.8
5 72.4 1670 1019 8.71
6 72.6 1245 1020 4.78
7 72.2 1900 1013 7.96 0.657
8 72.6 1250 1018
9 72.0 1660 1018
10 72.6 1900 1017
11 72.5 2000 1015
12 72.6 2130 1015
13 72.4 2430 1016
14 72.8 1100 1020 6.94 0.511
15 73.0 1950 1012
16 73.2 2010 1011
17 72.8 1790 1013
18 72.6 1920 1014
19 73.2 2150 1008
20 73.0 1355 1020
21 73.0 1670 1018 6.96 0.685
22 73.2 1640 1014
23 73.0 2490 1012
24 73.0 1840 1010
25 73.0 1340 1016
26 72.8 2040 1013
27 72.6 2320 1011
28 73.0
29 72.8 1600 1014 5.09 0.473
30 72.9 1480 1018 7.10
31 72.8 1960 1016 5.18
Apr. 1 72.6 2080 1013 5.74
2 72.5 2070 1010 3.35
3 72.6 1920 1018 6.68
Daily average from Nov. 2 1566 1016 7.84 0.642 1.58

[177]

COHN.

Date. Body-weight. Urine.
Volume. 24 hours. Sp. Gr. Nitrogen. Uric Acid. P₂O₅.
1903 kilos c.c. grams gram grams
Nov. 15 65.0 1140 1019 11.22
16 65.1 840 1024 10.86
daily
average
0.605
daily
average
1.60
daily
average
17 65.6 1280 1024
18 65.5 1420 1022
19 65.1 1500 1020
20 65.9 1540 1021
21 66.2 1340 1012
22 65.6 840 1026
23 65.5 1040 1018 8.85 0.542 1.26
24 65.9 1260 1021
25 66.1 1500 1016
26 65.8 800 1027
27 65.3 840 1022
28 65.4 940 1016
29 65.7 1200 1023
30 65.6 1480 1016 9.89 0.621 1.51
Dec. 1 64.8 740 1024
2 65.3 600 1026
3 64.8 920 1023
4 65.0 940 1020
5 64.8 680 1029
6 64.8 1460 1016
7 64.9 940 1027 8.60 0.392 1.32
8 65.0 900 1023
9 65.0 1040 1018
10 64.9 960 1021
11 64.0 580 1033
12 64.8 860 1026
13 64.0 660 1028
14 64.0 1060 1021 7.29 0.424 1.29
15 63.9 880 1019
16 63.9 470 1031
17 63.9 760 1026
18 64.3 1180 1020
19 64.4 1760 1011
20 64.0 1100 1017
21 64.4 615 1025 7.50 0.424
22 64.0 1050 1018
23 64.0 860 1019
24 64.2 1420 1019
[178] 25 64.2 1690 1017
26 64.0 740 1026
27 63.9 1370 1017
28 63.7 690 1025 7.70 0.358 0.90
29 63.6 1065 1024
30 64.0 960 1024
31 64.0 700 1026
1904
Jan. 1 63.4 1630 1017
2 63.5 460 1030
3 63.0 970 1031
4 63.4 1365 1012 8.03 0.498 1.12
5 63.5 980 1021
6 64.0 1175 1022
7 64.1 1250 1017
8 64.0 1500 1018
9 63.3 920 1027
10 63.3 1250 1019
11 63.3 880 1022 8.08
12 62.8 510 1026 6.49 0.510
13 63.0 900 1024 9.10 0.679
14 62.8 630 1026 7.33 0.523
15 62.4 950 1025 8.04 0.497
16 62.6 1300 1018 8.58 0.473
17 62.4 905 1026 7.44 0.431
18 62.0 835 1026 8.97 0.552 1.43
19 62.7 1510 1020
20 63.0 980 1023
21 62.4 935 1026
22 62.6 1610 1019
23 62.7 970 1024
24 62.2 1275 1020
25 63.0 1600 1017 7.34 0.539 1.30
26 62.3 770 1025
27 62.2 940 1023
28 62.4 980 1021
29 62.0 705 1025
30 62.9 890 1024
31 63.4 1560 1020
Feb. 1 63.5 1040 1028 8.15 0.532 1.37
[179] 2 63.4 960 1026
3 63.0 1500 1022
4 63.2 1430 1023
5 63.6 1890 1018
6 63.0 730 1025
7 63.0 920 1026
8 63.3 935 1027 8.00 0.522
9 64.0 1625 1016
10 63.5 1615 1017
11 64.0 1325 1020
12 64.0 1275 1021
13 64.0 770 1024
14 63.4 940 1023
15 63.5 1300 1027 8.59 0.510
16 63.1 1430 1020
17 63.6 1280 1024
18 63.3 870 1025
19 63.2 1250 1026
20 63.1 1250 1017
21 63.5 900 1016
22 63.3 1345 1026 8.45 0.633
23 63.5 1185 1019
24 63.3 1560 1020
25 63.4 1200 1015
26 63.0 750 1029
27 63.5 1140 1019
28 63.4 1220 1020
29 63.6 1160 1023 9.74
Mar. 1 63.5 900 1025 6.86
2 63.5 1030 1020 7.29
3 62.7 920 1021 6.40 0.480
4 62.7 1225 1014 5.59
5 62.5 1170 1026 9.55
6 62.6 940 1025 6.77
7 62.5 900 1026 8.41 0.608
8 63.0 1230 1020
9 62.7 1260 1020
10 62.5 980 1019
11 62.4 1150 1024
12 62.4 830 1027
[180] 13 62.4 1500 1020
14 62.0 825 1025 7.59 0.488
15 62.5 1200 1017
16 62.5 1490 1018
17 62.5 1145 1021
18 63.7 975 1021
19 63.0 825 1023
20 63.5 1450 1020
21 63.6 1480 1018 7.74 0.654
22 63.0 1100 1025
23 62.6 1050 1023
24 62.7 1050 1025
25 62.0 900 1027
26 62.4 750 1025
27 62.6 1530 1016
28 62.0 1060 1023 6.61 0.399
29 62.4 1460 1020 6.48
30 62.4 1020 1023 6.36
31 62.6 1730 1022 7.47
Apr. 1 62.4 895 1022 4.35
2 62.4 1465 1014 5.11
3 62.6 1165 1023 9.37
Daily average from Nov. 22 1092 1022 8.05 0.512 1.28

[181]

LOEWENTHAL.

Date. Body-weight. Urine.
Volume. 24 hours. Sp. Gr. Nitrogen. Uric Acid. P₂O₅.
1903 kilos c.c. grams gram grams
Oct. 4 60.1 960 1025 15.78 0.606 1.78
5 60.1 780 1025 10.90
6 60.3 820 1024 11.23 0.576 0.96
7 60.0 980 1022 14.99
8 60.0 1080 1019 11.34 0.351 1.55
9 60.0 990 1025 13.07
10 60.0 1120 1021 12.37
11 59.8 930 1019 10.83 0.389 1.05
12 60.4 1580 1022 17.06
13 60.2 1380 1017 13.00 0.516 2.13
14 61.0 640 1026 7.41
15 61.2 1220 1026 15.66 0.674 1.68
16 60.8 1060 1024 15.01
17 60.5 1130 1021 13.63
18 60.4 1580 1016 12.70 0.520 1.59
19 60.0 1350 1022 17.82
20 59.8 1250 1019 13.72 daily av. 0.489 daily av. 1.95 daily av.
21 60.0 1120 1024
22 60.4 1060 1025
23 61.0 1800 1020
24 61.2 1320 1021
25 61.4 1620 1015
26 62.4 1160 1024 9.80 0.430 1.40
27 62.6 1520 1021
28 62.6 860 1022
29 63.4 660 1024
30 62.5 1200 1023
31 62.2 920
Nov. 1 62.4 1050 1019
2 62.6 1330 1023 8.23 0.401 1.60
3 62.0 1020 1022
4 61.8 920 1020
5 62.4 580 1029
6 62.4 1400 1016
7 62.0 780 1022
8 61.9 760 1021
9 61.8 840 1031 8.28 0.390 1.34
10 60.5 440 1028
11 61.0 1060 1028
12 61.2 880 1027
[182] 13 61.4 320 1023
14 61.4 660 1023
15 61.2 1020 1023
16 61.4 960 1025 8.62 0.349 1.30
17 61.0 680 1028
18 61.0 940 1023
19 60.9 880 1024
20 61.5 1540 1018
21 61.7 1220 1022
22 61.2 1120 1022
23 61.1 1440 1014 8.36 0.392 1.43
24 60.2 840 1024
25 60.3 680 1026
26 60.8 900 1022
27 60.5 860 1025
28 60.3 800 1023
29 60.3 1040 1025
30 60.8 1040 1021 7.59 0.408 1.26
Dec. 1 60.4 1120 1017
2 60.0 660 1027
3 59.9 900 1022
4 59.5 1120 1025
5 59.0 400 1028
6 58.6 480 1033
7 58.2 960 1027 9.03 0.379 1.49
8 58.0 800 1020 8.78
9 58.6 700 1028 10.04
10 60.0 1000 1019 9.06
11 60.0 800 1025 8.71
12 60.0 680 1032 7.51
13 59.5 620 1030 7.74
14 59.5 940 1022 6.90 0.408 1.14
15 59.0 920 1019
16 59.6 690 1027
17 59.3 800 1020
18 59.7 1145 1020
19 59.7 1110 1016
20 59.0 840 1020
21 59.0 775 1025 6.29 0.275
22 58.4 510 1027
[183] 23 59.2 700 1026
24 59.0 890 1015
25 58.3 900 1027
26 59.0 930 1015
27 58.4 990 1018
28 58.5 672 1028 6.92 0.515 1.17
29 58.4 795 1023
30 59.0 870 1025
31 58.8 920 1027
1904
Jan. 1 58.7 1340 1022
2 58.2 1232 1019
3 58.6 842 1025
4 58.8 1030 1017 7.27 0.344 0.97
5 58.6 1020 1026
6 58.8 890 1024
7 59.0 1350 1016
8 57.7 900 1026
9 58.0 735 1033
10 57.9 760 1024
11 58.0 795 1021 6.68
12 58.2 1110 1017 7.33 0.383
13 58.1 1190 1015 7.64 0.379
14 57.0 620 1027 6.21 0.415
15 57.2 825 1028 8.18 0.409
16 57.8 1100 1019 7.92 0.305
17 57.5 1185 1021 7.26 0.338
18 57.3 630 1019
19 57.5 525 1030 6.84 0.321 0.99
20 58.0 1050 1026
21 57.7 790 1027
22 57.7 850 1030
23 57.4 605 1024
24 57.4 800 1030
25 57.9 1050 1020 6.83 0.312 1.14
26 58.0 850 1026
27 58.2 1270 1018
28 59.0 1255 1013
29 58.0 615 1028
30 58.0 1025 1029
[184] 31 58.6 1120 1026 7.27 0.411 1.57
Feb. 1 58.4 1025 1029
2 58.7 1300 1023
3 58.4 1170 1024
4 58.4 1350 1029
5 59.0 1250 1026
6 58.8 1160 1019
7 58.4 825 1029 7.61 0.416
8 58.5 830 1028
9 58.5 1095 1025
10 59.0 1140 1027
11 59.2 1330 1020
12 58.5 1020 1029
13 59.0 1075 1025
14 59.0 1030 1024 8.00 0.336
15 58.3 1150 1027
16 58.4 1270 1024
17 58.6 1490 1020
18 59.0 1060 1027
19 58.8 620 1026
20 58.9 930 1029
21 59.1 885 1029 6.84 0.449
22 59.3 1320 1023
23 59.4 1490 1016
24 59.4 1195 1019
25 59.4 2100 1011
26 58.4 860 1023
27 58.4 955 1027
28 58.4 1045 1027
29 58.2 1000 1027 7.38 0.348
Mar. 1 58.6 1040 1024 7.05
2 58.5 880 1028 7.07
3 58.7 890 1026 7.85
4 58.5 965 1026 7.35
5 58.6 730 1022 4.29
6 58.7 1170 1027 8.07
7 58.3 920 1026 6.97 0.333
8 58.9 970 1026
9 58.8 940 1026
10 58.9 1600 1017
[185] 11 59.0 1290 1020
12 59.0 820 1029
13 58.9 990 1026
14 59.5 1620 1019 7.34 0.265
15 59.0 1250 1023
16 59.0 1360 1018
17 59.1 1160 1021
18 59.0 1450 1019
19 59.1 1650 1018
20 59.0 1350 1021
21 59.0 1110 1024 6.37 0.427
22 58.8 1250 1021
23 58.6 1150 1021
24 58.6 760 1025
25 59.0 1100 1025
26 58.6 990 1028
27 58.5 1150 1026
28 58.6 1175 1024 6.27 0.341
29 59.0 1295 1025 7.54
30 59.0 1570 1018 7.07
31 59.2 1120 1024 5.24
Apr. 1 59.0 1260 1022 6.43
2 59.0 1550 1020 6.33
3 59.0 1710 1022 9.85
Daily average from Nov. 2 1007 1024 7.83 0.372 1.28

[186]

ZOOMAN.

Date. Body-weight. Urine.
Volume. 24 hours. Sp. Gr. Nitrogen. Uric Acid. P₂O₅.
1903 kilos c.c. grams gram grams
Oct. 4 54.0 540 1026 8.88 0.434 0.56
5 54.0 940 1027 15.28
6 53.6 1140 1024 16.42 0.730 2.21
7 54.5 1640 1016 17.52
8 54.4 930 1017 10.10 0.275 1.21
9 54.4 1160 1022 15.80
10 54.3 1080 1019 15.24
11 54.5 1340 1014 13.65 0.450 1.73
12 54.8 1080 1022 11.73
13 55.4 1140 1022 13.48 0.839 1.70
14 55.7 1020 1018 9.85
15 55.2 1560 1021 20.40 0.779 2.92
16 56.0 1240 1024 17.33
17 55.6 1070 1025 16.11
18 55.6 1730 1017 20.86 0.736 2.26
19 55.4 1370 1020 18.57
20 55.6 1290 1024 15.38
daily
average
0.683
daily
average
1.87
daily
average
21 55.6 1120 1025
22 55.8 1140 1023
23 55.9 1120 1025
24 56.2 1600 1020
25 56.5 1620 1015
26 56.6 1140 1024 11.70 0.583 1.56
27 56.6 1770 1015
28 56.6 960 1021
29 57.3 1120 1019
30 56.8 1160 1019
31 57.0 820
Nov. 1 56.9 1730 1016
2 56.5 750 1026 10.01 0.564 1.39
3 57.1 1380 1018
4 57.1 1040 1019
5 56.6 900 1018
6 56.6 1220 1016
7 56.2 640 1026
8 55.8 900 1020
9 56.1 1100 1021 8.76 0.512 1.33
10 56.2 680 1024
11 56.4 660 1016
12 56.7 1320 1024
[187] 13 56.7 420 1024
14 56.0 920 1029
15 56.0 1540 1015
16 55.7 1080 1022 7.79 0.398 1.02
17 54.4 700 1027
18 54.6 700 1025
19 54.8 700 1025
20 55.4 940 1021
21 55.2 740 1025
22 54.7 720 1023
23 54.5 740 1014 7.44 0.420 1.06
24 54.0 860 1025
25 54.3 620 1025
26 54.4 980 1023
27 54.5 940 1024
28 54.3 460 1026
29 54.4 1000 1018
30 54.0 980 1022 10.26 0.494 1.45
Dec. 1 54.2 1120 1020
2 54.2 940 1017
3 54.0 1200 1018
4 54.0 1080 1024
5 53.9 640 1031
6 54.0 960 1026
7 54.1 880 1028 10.15 0.423 1.39
8 54.6 680 1029
9 54.6 680 1030
10 55.0 1220 1019
11 54.7 920 1028
12 55.1 780 1028
13 54.7 1140 1020
14 54.4 840 1021 7.66 0.389 1.20
15 54.0 1200 1016
16 54.0 860 1021
17 54.5 1140 1018
18 54.0 820 1022
19 54.1 980 1018
20 54.0 885 1023
21 54.0 660 1027 8.26 0.401 0.78
22 53.5 570 1025
[188] 23 54.0 770 1028
24 54.0 920 1025
25 54.3 1320 1018
26 54.7 1075 1020
27 54.5 1240 1018
28 54.1 880 1022 8.00 0.440 0.88
29 54.0 1080 1019
30 54.3 775 1029
31 54.4 1010 1023
1904
Jan. 1 54.0 900 1022
2 53.6 625 1026
3 53.9 730 1026
4 53.0 1030 1019 7.24 0.379 1.15
5 53.4 1100 1022
6 54.0 980 1020
7 54.0 860 1022
8 54.0 960 1026
9 53.5 695 1025
10 54.0 980 1016
11 53.5 930 1020 8.98 0.632
12 53.8 1030 1023 11.31 0.657
13 53.6 980 1024 11.63 0.445
14 53.5 1150 1017 9.38 0.443
15 53.0 700 1030 8.44 0.442
16 53.4 920 1020 8.89 0.381
17 53.5 1270 1019 8.99
18 53.5 1180 1020 7.78 0.428 1.27
19 53.6 755 1026
20 53.6 1190 1015
21 53.0 800 1030
22 53.2 660 1030
23 53.4 770 1025
24 53.4 1035 1017
25 53.6 1250 1013 6.87 0.302 1.18
26 54.0 1140 1024
27 54.2 1170 1018
28 54.6 1120 1018
29 54.5 690 1026
30 54.5 1020 1025
[189] 31 54.8 1320 1019
Feb. 1 54.3 1060 1026 8.15 0.405 1.31
2 54.5 1170 1019
3 54.5 1350 1022
4 54.3 1280 1022
5 54.0 1015 1025
6 54.6 1610 1014
7 54.3 1010 1028
8 54.6 1065 1026 8.37 0.497
9 55.0 925 1027
10 55.0 1195 1023
11 55.0 880 1024
12 55.0 960 1016
13 55.2 1565 1020
14 55.0 1415 1023
15 55.0 1060 1029 9.34 0.408
16 54.8 1130 1025
17 55.0 1910 1019
18 55.2 1260 1020
19 55.0 970 1027
20 54.4 670 1031
21 54.7 1070 1022
22 54.4 760 1025 7.38 0.559
23 54.6 1225 1020
24 55.2 1050 1026
25 55.2 730 1027
26 55.4 1145 1019
27 55.0 990 1021
28 54.9 985 1026
29 55.0 765 1027 7.02 0.401
Mar. 1 55.3 810 1024 6.66
2 55.0 880 1027 7.26
3 54.8 1020 1020 7.59
4 54.5 955 1025 7.51
5 54.0 1035 1020 7.08
6 54.0 880 1027 6.81
7 54.7 885 1023 8.24 0.428
8 55.0 970 1017
9 54.6 940 1025
10 54.7 1460 1022
[190] 11 55.0 1340 1017
12 54.7 1180 1023
13 55.0 1040 1021
14 55.0 1270 1016 7.90 0.455
15 54.8 900 1023
16 55.0 1145 1019
17 55.0 1155 1018
18 53.0 1480 1016
19 55.2 1355 1023
20 54.6 1000 1023
21 54.7 750 1026 7.57 0.586
22 55.0 1270 1018
23 55.0 1090 1016
24 55.0 1080 1025
25 54.8 1080 1028
26 55.0 980 1021
27 55.2 1110 1020
28 55.2 1270 1019 7.47
29 55.2 1160 1024 7.80
30 55.0 1140 1018 5.40
31 55.3 1340 1024 8.04
Apr. 1 55.0 1480 1019 8.44
2 55.1 1300 1023 7.10
3 55.0 1445 1018 8.15
Daily average from Nov. 2 1008 1022 8.25 0.457 1.19

[191]

BATES.

Date. Body-weight. Urine.
Volume. 24 hours. Sp. Gr. Nitrogen. Uric Acid. P₂O₅.
1903 kilos c.c. grams gram grams
Oct. 4 72.7 870 1033 14.56 0.651 2.18
5 72.7 1120 1022 13.13
6 72.4 760 1027 9.44 0.489 1.38
7 72.3 920 1022 12.86
8 72.0 630 1029 11.11 0.415 1.29
9 72.0 1030 1025
10 72.0 1230 1022 14.46
11 72.3 740 1024 10.79 0.397 1.44
12 72.3 860 1024 10.54
13 72.1 1040 1025 14.23 0.769 2.46
14 72.3 1010 1027 13.70
15 72.4 1300 1021 14.43 0.510 1.88
16 72.4 1040 1025 15.35
17 72.4 1440 1020 16.33
18 72.2 1420 1021 18.66 0.657 2.51
19 71.8 780 1026 13.14
20 71.3 1060 1027 14.21
daily
average
0.517
daily
average
1.26
daily
average
21 72.0 1020 1025
22 72.5 1080 1024
23 72.4 1200 1024
24 72.4 1100 1025
25 72.4 1030 1024
26 72.4 1060
27 72.6 1020 1022 9.20 0.409 1.27
28 72.4 720 1027
29 72.4 400 1032
30 72.3 720 1027
31 72.3 720
Nov. 1 72.3 820 1027
2 72.0 960 1026 9.01 0.487 1.53
3 72.4 920 1025
4 71.9 700 1025
5 71.6 900 1012
6 71.5 700 1029
7 70.5 600 1023
8 70.0 680 1031
9 70.3 660 1026 7.97 0.460 1.20
10 70.6 660 1028
11 70.6 560 1030
12 71.0 740 1027
[192] 13 71.0 660 1027
14 70.6 480 1032
15 70.4 800 1026
16 70.8 860 1025 6.94 0.374 1.04
17 70.0 860 1023
18 69.8 540 1025
19 69.4 700 1026
20 70.3 1080 1023
21 70.2 640 1025
22 69.3 720 1027
23 69.1 720 1025 8.04 0.394 1.56
24 68.7 600 1028
25 68.7 620 1028
26 69.0 840 1031
27 68.6 820 1026
28 67.9 800 1022
29 69.4 700 1027
30 69.0 780 1025 8.24 0.393 1.37
Dec. 1 68.5 760 1026
2 68.7 640 1027
3 68.1 940 1027
4 69.0 540 1023
5 68.0 1360 1011
6 69.0 880 1027
7 67.9 960 1026 10.14 0.392 1.57
8 68.2 700 1026 7.85
9 68.0 800 1025 10.45
10 68.7 700 1027 8.74
11 67.9 780 1028 9.27
12 68.0 820 1029 8.85
13 67.6 860 1028 9.44
14 67.8 700 1029 7.36
15 67.4 540 1028 6.51
16 67.4 640 1032 7.61 0.367 1.36
17 67.6 680 1027
18 68.8 1000 1023
19 68.3 800 1023
20 67.0 660 1027
21 67.0 595 1027 6.77 0.345
22 66.2 560 1028
[193] 23 66.5 660 1027
24 66.4 610 1021
25 65.6 1057 1021
26 66.0 700 1029
27 66.2 755 1026
28 65.8 740 1024 6.53 0.269 0.80
29 65.5 710 1026
30 66.0 900 1025
31 65.7 710 1028
1904
Jan. 1 65.7 690 1027
2 65.3 1015 1010
3 65.0 850 1027
4 65.0 730 1024 8.54 0.405 1.13
5 65.1 835 1022
6 65.6 1045 1027
7 66.2 900 1024
8 65.4 1030 1025
9 66.0 840 1028
10 66.0 965 1025
11 65.8 700 1026 6.80
12 66.5 740 1025 7.46 0.365
13 65.2 630 1027 7.03 0.399
14 64.5 550 1028 7.13 0.357
15 64.6 680 1022 8.04 0.434
16 65.0 620 1029 7.66 0.470
17 65.0 925 1024 7.38 0.347
18 65.0 590 1032 6.69 0.356 0.80
19 65.0 650 1028
20 64.8 575 1029
21 64.4 735 1028
22 64.8 640 1029
23 64.6 760 1026
24 64.3 870 1023
25 64.0 740 1027 8.54 0.359 1.27
26 64.5 975 1024
27 63.8 910 1024
28 64.0 600 1030
29 63.8 1300 1017
30 64.0 1135 1024
[194] 31 64.0 1460 1018
Feb. 1 64.0 910 1027 9.19 0.362 1.07
2 63.9 1250 1021
3 63.5 1080 1026
4 63.5 970 1024
5 63.6 1250 1024
6 64.0 1260 1018
7 64.0 785 1026
8 64.6 1235 1022 9.94
9 64.3 1460 1018
10 64.2
11 64.3
12 64.3
Daily average from Oct. 27 805 1025 8.08 0.387 1.23

[195]

DAVIS.

Date. Body-weight. Urine.
Volume. 24 hours. Sp. Gr. Nitrogen. Uric Acid. P₂O₅.
1903 kilos c.c. grams gram grams
Oct. 4 59.3 2030 1014 15.15 0.672 1.99
5 59.3 1160 1020 10.99
6 59.0 850 1024 9.38 0.503 1.26
7 59.1 1860 1012 13.95
8 59.3 960 1021 9.33 0.398 1.47
9 58.3 900 1027 11.56
10 58.3 1660 1017 17.23
11 58.7 1460 1019 16.02 0.724 2.27
12 58.5 1060 1022 11.82
13 59.4 1920 1014 16.59 0.689 2.53
14 59.4 1460 1022 13.14
15 58.9 1320 1021 13.38 0.493 1.53
16 58.9 1900 1015 17.10
17 59.0 1410 1019 14.55
18 59.5 1650 1017 15.25 0.647 1.92
19 59.1 1120 1022 13.37
20 58.2 1150 1020 11.56
daily
average
0.480
daily
average
1.50
daily
average
21 58.2 980 1021
22 59.1 1320 1022
23 59.4 1320 1016
24 58.6 1160 1022
25 59.2 1300 1013
26 59.0 860 1024 9.20 0.474 1.35
27 59.2 1240 1024
28 59.4 1440 1014
29 59.5 820 1022
30 59.4 1000 1017
31 59.2 920
Nov. 1 59.4 1120 1015
2 58.7 840 1026 9.07 0.474 1.48
3 59.1 1290 1018
4 59.0 680 1025
5 58.5 305 1027
6 58.4 700 1023
7 58.7 780 1022
8 58.5 1720 1011
9 58.2 1320 1015 8.33 0.422 1.38
10 58.9 920 1020
11 59.3 1640 1014
12 58.9 780 1024
[196] 13 59.0 940 1025
14 59.0 1180 1016
15 59.0 1900 1013
16 58.8 1080 1022 9.60 0.398 1.50
17 59.0 1080 1018
18 58.4 1500 1017
19 58.2 1260 1018
20 58.1 1220 1025
21 58.7 1120 1022
22 58.7 1100 1021
23 58.6 1140 1017 9.00 0.447 1.52
24 58.4 1360 1017
25 58.3 1700 1010
26 58.2 1120 1023
27 59.4 1620 1017
28 58.0 700 1027
29 58.7 1660 1025
30 58.5 800 1025 11.41 0.417 2.12
Dec. 1 58.0 700 1020
2 57.4 680 1028
3 57.0 640 1028
4 57.0 940 1032
5 56.2 660 1032
6 56.0 800 1029
7 56.0 800 1026 8.91 0.412 1.43
8 56.1 780 1030
9 57.0 820 1022
10 58.0 500 1025
11 57.1 580 1029
12 57.3 820 1031
13 57.8 580 1027
14 57.5 740 1027 7.96 0.413 1.50
15 57.5 1680 1015
16 57.9 900 1021
17 57.4 780 1013
18 56.9 800 1026
19 57.4 730 1025
20 57.4 800 1023
21 57.4 1310 1017 7.35 0.319
22 57.0 1370 1014
[197] 23 57.0 980 1020
24 57.0 865 1016
25 57.4 1300 1017
26 58.0 1390 1017
27 57.3 1340 1018
28 57.6 875 1019 6.83 0.413 0.99
29 57.0 680 1020
30 56.8 685 1029
31 56.7 815 1026
1904
Jan. 1 57.4 1150 1015
2 57.9 1610 1023
3 58.6 1120 1023
4 58.3 1350 1011 7.04 0.372 0.95
5 57.8 1255 1017
6 58.0 925 1022
7 58.6 1120 1016
8 58.4 1350 1020
9 57.7 890 1026
10 58.6 1510 1012
11 57.9
12 57.2 835 1017 8.32 0.408
Daily average from Oct. 26 1045 1021 8.61 0.414 1.42

[198]

Any elaborate discussion of the individual results, tabulated in the foregoing tables, seems hardly necessary. To any one interested in the details of the work, a study of the tables themselves will give the necessary information. It may be well, however, to emphasize at once a few of the fundamental points most striking in character which bear upon the main problem. Take, for instance, the case of Oakman, where the data are recorded for every day from October 4, 1903, to April 4, 1904. The degree of proteid metabolism, as indicated by the excretion of nitrogen through the kidneys, is here shown for each day of the six months. Up to November 3, practically for a month, there was not observable any very noticeable change in the rate of proteid metabolism, but commencing with November 4, the nitrogen excretion dropped very rapidly, and as one glances through the daily records for month after month, it is seen that the daily nitrogen output through the kidneys fell to 6 to 8 grams per day, with a daily average excretion of 7.42 grams of nitrogen, as figured from October 21 to April 4.

Further, it will be noted that while the body-weight gradually declined during the first three months, falling from 66.7 kilos down to 62.3 kilos on January 18, from that date on to the close of the experiment the body-weight was practically constant. Here, then, we see, under the use of a prescribed diet quite sufficient in amount to satisfy the cravings of the appetite, a lowering of proteid metabolism equal to that obtained by the individuals of the preceding group. Again, if the body-weight of Oakman is placed at 64 kilos, as representing the average between the initial body-weight and the weight during the last three months, it will be found that the output of metabolized nitrogen per kilo of body-weight amounted to 0.116 gram; not widely different from similar data obtained with men of the preceding group.

FRITZ

Photograph taken at the close of the experiment.

Moreover, these results obtained with Oakman are practically duplicated by every other member of this group of soldiers detailed from the United States Army. No exception whatever is to be seen, but every man shows the same lowered[199] proteid metabolism, with practical maintenance of body-weight, with complete satisfying of the appetite, and without loss of health, strength, or vigor, as will be enlarged upon later.

While in the case of Oakman, the nitrogen excreted was determined by an analysis made each day, in the case of the other men of this group the data are given mainly for weekly periods; the results being expressed, however, in the average daily amount for each seven days’ period. By comparing the figures for the daily excretion of nitrogen with the daily dietary, it is easy to trace out the influence of the changes in diet on the extent of nitrogen metabolism.

In considering the changes in the rate of proteid metabolism shown by all the members of this group, it will suffice for present purposes to deal mainly with the average results.

Compare now the average daily output of nitrogen through the urine from November 1 until April 4—a period of five months—of each of these men.

AVERAGE DAILY OUTPUT OF NITROGEN.

Morris 7.03 = 7.80 grams Nitrogen as the grand average.
Steltz 7.13
Broyles 7.26
Loewenthal 7.38
Oakman 7.42
Fritz 7.84
Cohn 8.05
Coffman 8.17
Zooman 8.25
Sliney 8.39
Henderson 8.91
Bates 8.08 Oct. 27-Feb. 11.
Davis 8.61 Oct. 26-Jan. 12.

The figures given show an astonishingly low proteid metabolism for the five months’ period; 7.5 grams of nitrogen in the day’s urine correspond to 46.8 grams of proteid metabolized, while 8.5 grams of nitrogen mean the metabolism of 53.1[200] grams of proteid. In other words, all of these men during a period of five months practically averaged a daily output of nitrogen through the kidneys corresponding to the metabolism of less than one-half the 105 grams of absorbable proteid called for by the so-called standard diets. Further, close scrutiny of the results in the individual tables shows that during many weeks much lower results were obtained than is indicated by the general averages.

Just here emphasis should be laid upon one fact, doubtless of primary importance in any modification of the rate or extent of metabolism in any individual, viz., that in this experiment the daily diet was prescribed, thereby taking from the individual freedom of choice in the selection of food. The writer has no question in his own mind that an intelligent choice of food, coupled with the satisfying of a natural or acquired appetite in moderation, will lead to better results than any system of prescription as to what shall be eaten each day and in what quantity. Still, this is the method necessarily made use of in the present experiment, the writer having prescribed the character and amount of each meal throughout the entire six months’ period, with due regard, of course, to the expressed likes and dislikes of the men.

One feature in the diet compelled by the circumstances of the case also needs to be referred to, namely, the necessity of keeping the men thoroughly satisfied, so that there should be no feeling of hunger, no craving for food. With a person interested in the experiment and desirous of ascertaining the effect of a low nitrogen intake, there would naturally be a willingness to endure, if necessary, for a time some personal discomfort; but with this detail of the United States Army it could not be expected that the men would remain satisfied if they were compelled to undergo the pangs of hunger even for a day or two. Consequently, it was necessary in prescribing the daily diet to see that the quantity of the food was such as to completely satisfy the appetite. This necessitated the use of considerable bulky food of low fuel, and low nitrogen, value. In this way only was it feasible to reduce the[201] nitrogen intake, as well as the fuel value of the food, to the desired level. Practically during the entire six months’ period, with the possible exception of a few days, the men were given sufficient food to completely satisfy their appetites. Throughout the entire period of the experiment, the men all manifested a keen appetite and utilized their food to good advantage, with establishment of the nitrogen metabolism indicated by the foregoing results.

Still confining our attention to the average results regarding nitrogen excretion, we may ask the question, what was the excretion of metabolized nitrogen per kilo of body-weight in the different individuals? This is easily calculated and the data are shown in the following table, in which the figures standing for body-weight are either the data for the month of April, 1904, or else the average between the October and April weights, as in those cases where the body-weight fell off during the experiment.

Body-weight. Average daily
Output of Nitrogen.
November-April.
Metabolized Nitrogen
per kilo
Body-weight.
kilos grams gram
Fritz 74.0 7.84 0.106
Oakman 64.0 7.42 0.116
Bates 68.0 8.08 0.118
Morris 59.0 7.03 0.119
Broyles 60.0 7.26 0.120
Henderson 71.0 8.91 0.125
Loewenthal 59.0 7.38 0.125
Cohn 63.5 8.05 0.126
Steltz 53.0 7.13 0.134
Sliney 60.0 8.39 0.138
Coffman 58.0 8.17 0.140
Davis 58.0 8.61 0.148
Zooman 55.0 8.25 0.150

Scrutiny of these results shows that the daily excretion of metabolized nitrogen ranged in this period of five months from 0.106 gram per kilo of body-weight up to 0.150 gram per kilo of body-weight. Since these men were on essentially the[202] same diet, it is obvious that there were some peculiarities, or personal idiosyncrasies, that tended to modify the exact extent of proteid metabolism, and in some cases at least constituted a more potent factor than body-weight in determining the rate of metabolism. This fact is clearly emphasized in the case of Morris, who, with a body-weight of 59 kilos, showed a proteid metabolism equivalent to only 7.03 grams of nitrogen per day, and Coffman, who, with a body-weight of 58 kilos, showed under the same conditions an average excretion of 8.17 grams of nitrogen per day.

What was the effect of this lowered proteid metabolism upon the bodily condition, especially body-weight? To answer this question the weights of the men are given in the following table, the one column of figures showing the body-weight at the commencement of the experiment, the other column showing the weight at the close of the experiment.

TABLE OF BODY-WEIGHTS.

October, 1903. April, 1904.
kilos kilos
Steltz 52.3 53.0
Zooman 54.0 55.0
Coffman 59.1 58.0
Morris 59.2 59.0
Broyles 59.4 61.0
Loewenthal 60.1 59.0
Sliney 61.3 60.6
Cohn 65.0 62.6
Oakman 66.7 62.1
Henderson 71.3 71.0
Fritz 76.0 72.6
Bates 72.7 64.3 February
Davis 59.3 57.2 January

Comparison of these figures shows that six of the men were practically of the same body-weight at the close of the experiment as at the beginning. Of the others, Oakman, Fritz, Cohn, and Bates lost somewhat. Bates, however, was quite stout, and[203] the work in the gymnasium as well as the change of diet tended to reduce his weight. In fact, with the possible exception of Oakman, the slight loss of weight these latter men underwent was a distinct gain to their bodily condition. The most significant feature, however, is to be found on scrutiny of the tables of results for each man, where is seen the body-weight for each day of the six months. Here it will be noticed that, as the experiment progressed, there was, as a rule, a tendency for the body-weight to increase; this was followed by a decline, after which the weight remained practically stationary. This is well illustrated in Oakman’s case. Starting with a body-weight of 66.7 kilos on October 4, he reached 67.6 kilos on November 29, then declining in weight to 62.3 on January 18, after which he remained practically stationary, or varied only within narrow limits.

Finally, it should be said that the low proteid metabolism on which these men were apparently maintaining body-weight was not associated with any increase of non-nitrogenous food. At no time did the fuel value of the daily food reach 3000 calories; in fact, about January 12 the average fuel value of the food was only a little over 2000 calories per day.

First Nitrogen Balance.

Early in January, the body-weight of the men having become practically stationary and the proteid metabolism, as measured by the output of metabolized nitrogen, having been reduced to a low level, an attempt was made to see if the men were truly in a condition of nitrogenous equilibrium. A six-day period was used, during which all the food for each meal was carefully analyzed, the nitrogen in every sample of food being determined in duplicate by the Kjeldahl-Gunning process. The fæces of the period were separated by lampblack, given at appropriate times in gelatin capsules, and all necessary precautions observed to insure an accurate nitrogen balance. The accompanying tables of results give all the necessary data.

[204]

The average nitrogen intake per day was 8.23 grams, and the average fuel value of the food per day was 2078 calories. These are the figures for Oakman. With some of the other men there were slight variations from these figures, as shown in the tables—owing to slight variations in diet. Without exception, all the men showed a minus balance, indicating that on this diet the body was losing nitrogen. In other words, the diet as a whole was insufficient for the needs of the body in every case. Whether this was due to lack of sufficient proteid or to an insufficient amount of fat and carbohydrate, i. e., a too low fuel value, cannot be said definitely, but there is every reason to believe that the amount of non-nitrogenous food was insufficient to furnish the requisite fuel value, and consequently body proteid was drawn upon to supply the deficiency. The loss of nitrogen to the body per day varied as a rule from 0.5 to 2.0 grams. In one case only, viz., Broyles, was there a close approach to a balance. In his case there was a minus balance of only 0.12 gram of nitrogen per day.

The average daily output of nitrogen through the urine for this six-days period (Oakman’s case) was 7.52 grams.

FRITZ

Photograph taken at the close of the experiment.

[205]

OAKMAN.

Tuesday, January 12, 1904.

Breakfast.—Fried Indian-meal 100 grams, syrup 50 grams, one cup coffee 350 grams, bread 50 grams, butter 15 grams.

Dinner.—Boiled macaroni 250 grams, stewed tomato 250 grams, bread 75 grams, one cup coffee 350 grams.

Supper.—Potato chips 100 grams, fried bacon 25 grams, bread 75 grams, jam 75 grams, one cup tea 350 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Fried Indian-meal 100 × 0.38 = 0.380 gram.
Syrup 50 × 0.051 = 0.025
Coffee (breakfast) 350 × 0.075 = 0.262
Butter 15 × 0.10 = 0.015
Macaroni 250 × 0.53 = 1.325
Stewed tomato 250 × 0.15 = 0.375
Bread 50 + 75 + 75 = 200 × 1.48 = 2.960
Potato chips 100 × 1.09 = 1.090
Bacon 25 × 3.13 = 0.780
Jam 75 × 0.039 = 0.029
Tea 350 × 0.067 = 0.234
Coffee (dinner) 350 × 0.091 = 0.318
Total nitrogen in food 7.793 grams.
Total nitrogen in urine 6.000
Fuel value of the food 2404 calories.

[206]

Wednesday, January 13, 1904.

Breakfast.—Boiled rice 150 grams, milk 125 grams, sugar 30 grams, butter 10 grams, bread 30 grams, one cup coffee 350 grams.

Dinner.—Hamburg steak with plenty of bread, fat, and onions chopped together 150 grams, boiled potato 200 grams, apple sauce 200 grams, bread 75 grams, one cup coffee 350 grams.

Supper.—Fried rice 100 grams, syrup 50 grams, one cup tea 350 grams, bread 50 grams, butter 15 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Boiled rice 150 × 0.36 = 0.540 grams.
Milk 125 × 0.55 = 0.687
Sugar 30 × 0.00 = 0.000
Butter (breakfast) 10 × 0.10 = 0.010
Bread (breakfast) 30 × 1.66 = 0.498
Coffee (breakfast) 350 × 0.066 = 0.231
Hamburg steak, etc. 150 × 2.80 = 4.200
Potato 200 × 0.29 = 0.580
Apple sauce 200 × 0.067 = 0.134
Bread (dinner) 75 × 1.66 = 1.245
Coffee (dinner) 350 × 0.076 = 0.266
Fried rice 100 × 0.50 = 0.500
Syrup 50 × 0.051 = 0.025
Tea 350 × 0.066 = 0.231
Bread (supper) 50 × 1.66 = 0.830
Butter 15 × 0.10 = 0.015
Total nitrogen in food 9.992 grams.
Total nitrogen in urine 7.330
Fuel value of the food 2133 calories.

[207]

Thursday, January 14, 1904.

Breakfast.—Boiled hominy 150 grams, milk 125 grams, sugar 30 grams, butter 10 grams, bread 30 grams, one cup coffee 350 grams.

Dinner.—Split pea soup (thick) 200 grams, bread 75 grams, mashed potato 100 grams, pickles 30 grams, one cup coffee 350 grams, pie 120 grams.

Supper.—Suet pudding 150 grams, apple sauce 125 grams, crackers 25 grams, one cup tea 350 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Boiled hominy 150 × 0.21 = 0.315 gram.
Milk 125 × 0.52 = 0.650
Sugar 30 × 0.00 = 0.000
Butter 10 × 0.10 = 0.010
Bread (breakfast) 30 × 1.59 = 0.477
Coffee (breakfast) 350 × 0.096 = 0.336
Split pea soup 200 × 0.69 = 1.380
Bread (dinner) 75 × 1.59 = 1.192
Mashed potato 100 × 0.31 = 0.310
Pickles 30 × 0.054 = 0.016
Coffee (dinner) 350 × 0.075 = 0.262
Pie 120 × 0.50 = 0.600
Suet pudding 150 × 0.78 = 1.170
Apple sauce 125 × 0.058 = 0.072
Crackers 25 × 1.61 = 0.402
Tea 350 × 0.063 = 0.220
Total nitrogen in food 7.412 grams.
Total nitrogen in urine 8.290
Fuel value of the food 2000 calories.

[208]

Friday, January 15, 1904.

Breakfast.—Wheat griddle cakes 200 grams, syrup 50 grams, one cup coffee 350 grams.

Dinner.—Codfish-balls (4 parts potato, 1 part fish, fried in pork fat) 150 grams, stewed tomato 200 grams, bread 75 grams, one cup coffee 350 grams, apple pie 95 grams.

Supper.—Apple fritters 200 grams, stewed prunes 125 grams, bread 50 grams, butter 15 grams, one cup tea 350 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Wheat griddle cakes 200 × 0.78 = 1.560 grams.
Syrup 50 × 0.051 = 0.025
Coffee (breakfast) 350 × 0.075 = 0.262
Codfish-balls, etc. 150 × 1.77 = 2.655
Stewed tomato 200 × 0.14 = 0.280
Bread (dinner) 75 × 1.59 = 1.192
Coffee (dinner) 350 × 0.075 = 0.262
Apple pie 95 × 0.40 = 0.380
Apple fritters 200 × 0.40 = 0.800
Stewed prunes 125 × 0.15 = 0.187
Bread (supper) 50 × 1.59 = 0.795
Butter 15 × 0.10 = 0.015
Tea 350 × 0.042 = 0.147
Total nitrogen in food 8.560 grams.
Total nitrogen in urine 7.140
Fuel value of the food 2030 calories.

[209]

Saturday, January 16, 1904.

Breakfast.—Soft oatmeal 150 grams, milk 100 grams, sugar 30 grams, bread 30 grams, butter 10 grams, one cup coffee 350 grams.

Dinner.—Baked macaroni with a little cheese 200 grams, stewed tomato 200 grams, bread 50 grams, tapioca-peach pudding 150 grams, one cup coffee 350 grams.

Supper.—French fried potato 100 grams, fried bacon 20 grams, bread 75 grams, jam 75 grams, one cup tea 350 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Soft oatmeal 150 × 0.27 = 0.405 grams.
Milk 100 × 0.44 = 0.440
Sugar 30 × 0.00 = 0.000
Bread (breakfast) 30 × 1.61 = 0.483
Butter 10 × 0.10 = 0.010
Coffee (breakfast) 350 × 0.075 = 0.262
Baked macaroni, etc. 200 × 0.72 = 1.440
Stewed tomatoes 200 × 0.15 = 0.300
Bread (dinner) 50 × 1.61 = 0.805
Tapioca-peach pudding 150 × 0.087 = 0.130
Coffee (dinner) 350 × 0.093 = 0.325
French fried potato 100 × 0.47 = 0.470
Fried bacon 20 × 3.15 = 0.630
Bread (supper) 75 × 1.61 = 1.207
Jam 75 × 0.039 = 0.029
Tea 350 × 0.099 = 0.346
Total nitrogen in food 7.282 grams.
Total nitrogen in urine 8.230
Fuel value of the food 1824 calories.

[210]

Sunday, January 17, 1904.

Breakfast.—Boiled Indian-meal 125 grams, milk 125 grams, sugar 30 grams, butter 10 grams, bread 30 grams, one cup coffee 350 grams.

Dinner.—Bean soup (thick) 200 grams, bread 75 grams, mashed potato 100 grams, pickles 25 grams, one cup coffee 350 grams, custard pie 105 grams.

Supper.—Crackers 50 grams, butter 15 grams, stewed prunes 125 grams, sponge cake 100 grams, one cup tea 350 grams.

Food. Grams. Per cent Nitrogen. Total Nitrogen.
Boiled Indian-meal 125 × 0.24 = 0.300 grams.
Milk 125 × 0.50 = 0.625
Sugar 30 × 0.00 = 0.000
Butter (breakfast) 10 × 0.10 = 0.010
Bread (breakfast) 30 × 1.61 = 0.483
Coffee (breakfast) 350 × 0.087 = 0.304
Bean soup 200 × 0.86 = 1.720
Bread (dinner) 75 × 1.61 = 1.207
Mashed potato 100 × 0.28 = 0.280
Pickles 25 × 0.054 = 0.013
Coffee (dinner) 350 × 0.081 = 0.283
Custard pie 105 × 0.88 = 0.924
Crackers 50 × 1.61 = 0.805
Butter (supper) 15 × 0.10 = 0.015
Stewed prunes 125 × 0.17 = 0.212
Sponge cake 100 × 1.00 = 1.000
Tea 350 × 0.048 = 0.168
Total nitrogen in food 8.349 grams.
Total nitrogen in urine 8.140
Fuel value of the food 2081 calories.

[211]

NITROGEN BALANCE.—Oakman.

Nitrogen
Taken in.
Output.
Nitrogen in Urine. Weight of Fæces (dry).
Jan. 12 7.793 grams. 6.00 grams.
13 9.992 7.33
14 7.412 8.29 5.0 grams.
15 8.560 7.14 76.0
16 7.282 8.23 13.5
17 8.349 8.14 9.5
104.0 grams contain
7.39% N.
49.388 45.13 + 7.685 grams nitrogen.
49.388 grams nitrogen. 52.815 grams nitrogen.
Nitrogen balance for six days = -3.427 grams.
Nitrogen balance per day = -0.571 gram.

Average Intake.

Calories per day 2078.
Nitrogen per day 8.23 grams.

[212]

NITROGEN BALANCE.—Loewenthal.

Nitrogen
Taken in.
Output.
Nitrogen in Urine. Weight of Fæces (dry).
Jan. 12 7.793 grams. 7.33 grams.
13 9.992 7.64 21 grams.
14 7.388 6.21 26
15 8.560 8.18 52
16 7.282 7.92 37
17 8.349 7.26 11
147 grams contain
6.97% N.
49.364 44.54 + 10.24 grams nitrogen.
49.364 grams nitrogen. 54.78 grams nitrogen.
Nitrogen balance for six days = -5.416 grams.
Nitrogen balance per day = -0.902 gram.

Daily diet same as Oakman’s, except that a smaller amount of coffee was taken at breakfast on the 14th. Nitrogen correction made accordingly.

COFFMAN STELTZ

Photographs taken at the close of the experiment.

[213]

NITROGEN BALANCE.—Steltz.

Nitrogen
Taken in.
Output.
Nitrogen in Urine. Weight of Fæces (dry).
Jan. 12 7.793 grams. 4.61 grams. 15.0 grams.
13 9.463 7.90 34.0
14 7.412 4.99 21.0
15 8.560 9.05 31.5
16 7.282 7.56 33.0
17 8.349 8.55 18.0
152.5 grams contain
6.52% N.
48.859 42.66 + 9.94 grams nitrogen.
48.859 grams nitrogen. 52.60 grams nitrogen.
Nitrogen balance for six days = -3.741 grams.
Nitrogen balance per day = -0.623 gram.

Daily diet same as Oakman’s, except on January 13, when 8 grams of boiled rice were uneaten at breakfast and 100 grams of fried rice at supper. Correction in nitrogen-content made accordingly.

[214]

NITROGEN BALANCE.—Bates.

Nitrogen
Taken in.
Output.
Nitrogen in Urine. Weight of Fæces (dry).
Jan. 12 7.706 grams. 7.46 grams.
13 9.916 7.03
14 7.375 7.13 36 grams.
15 8.439 8.04 30
16 7.226 7.66 34
17 8.349 7.38 34
134 grams contain
7.17% N.
49.011 44.70 + 9.61 grams nitrogen.
49.011 grams nitrogen. 54.31 grams nitrogen.
Nitrogen balance for six days = -5.299 grams.
Nitrogen balance per day = -0.883 gram.

Daily diet same as Oakman’s, with the following exceptions:

Jan. 12 Supper: 8 grams Potato chips, uneaten.
13 Dinner: 113 Apple sauce,
14 50 Coffee,
15 Supper: 81 Prunes,
16 Breakfast: 75 Coffee,

[215]

NITROGEN BALANCE.—Coffman.

Nitrogen
Taken in.
Output.
Nitrogen in Urine. Weight of Fæces (dry).
Jan. 12 7.793 grams. 8.82 grams.
13 9.992 8.28
14 7.412 8.30 57.00 grams.
15 8.560 7.91 41.25
16 7.282 7.32 47.00
17 8.349 7.44 21.50
166.75 grams contain
6.66% N
49.388 48.07 + 11.10 grams nitrogen.
49.388 grams nitrogen. 59.17 grams nitrogen.
Nitrogen balance for six days = -9.782 grams.
Nitrogen balance per day = -1.630 grams.

Daily diet same as Oakman’s.

[216]

NITROGEN BALANCE.—Fritz.

Nitrogen
Taken in.
Output.
Nitrogen in Urine. Weight of Fæces (dry).
Jan. 12 7.793 grams. 8.99 grams.
13 9.992 6.49
14 7.412 10.26 64.0 grams.
15 8.560 7.97 29.5
16 7.282 5.20 62.0
17 8.186 9.40 31.0
186.5 grams contain
6.49% N.
49.225 48.31 + 12.10 grams nitrogen.
49.225 grams nitrogen. 60.41 grams nitrogen.
Nitrogen balance for six days = -11.185 grams.
Nitrogen balance per day = -1.864 grams.

Daily diet same as Oakman’s, except that on the 17th inst. a portion of the prunes was uneaten. Correction made accordingly.

[217]

NITROGEN BALANCE.—Henderson.

Nitrogen
Taken in.
Output.
Nitrogen in Urine. Weight of Fæces (dry).
Jan. 12 7.639 grams. 7.68 grams.
13 9.794 8.22
14 7.487 8.24
15 8.560 7.76 45 grams.
16 7.068 7.56 26
17 8.045 7.87 22
93 grams contain
6.45% N.
48.593 47.33 + 6.00 grams nitrogen.
48.593 grams nitrogen. 53.33 grams nitrogen.
Nitrogen balance for six days = -4.737 grams.
Nitrogen balance per day = -0.789 gram.

Daily diet same as Oakman’s, except that on several days smaller amounts of coffee and tea were taken. Corrections made accordingly.

[218]

NITROGEN BALANCE.—Morris.

Nitrogen
Taken in.
Output.
Nitrogen in Urine. Weight of Fæces (dry).
Jan. 12 7.255 grams. 4.19 grams.
13 9.573 7.92
14 7.325 7.91 4.75 grams.
15 8.638 7.44 38.00
16 7.282 7.38 71.00
17 8.349 5.28 53.00
166.75 grams contain
6.45% N.
48.322 40.12 + 10.75 grams nitrogen.
48.322 grams nitrogen. 50.87 grams nitrogen.
Nitrogen balance for six days = -2.548 grams.
Nitrogen balance per day = -0.424 gram.

Daily diet same as Oakman’s except that on the first three days smaller amounts of tea and coffee were taken. Corrections made accordingly.

[219]

NITROGEN BALANCE.—Zooman.

Nitrogen
Taken in.
Output.
Nitrogen in Urine. Weight of Fæces (dry).
Jan. 12 7.466 grams. 11.31 grams.
13 9.992 11.63
14 7.412 9.38
15 8.560 8.44 27.5 grams.
16 7.282 8.89 28.5
17 8.349 8.99 13.0
69.0 grams contain
6.46% N.
49.061 58.64 + 4.45 grams nitrogen.
49.061 grams nitrogen. 63.09 grams nitrogen.
Nitrogen balance for six days = -14.029 grams.
Nitrogen balance per day = -2.338 gram.

Daily diet same as Oakman’s, except that on January 12th 30 grams potato chips were not eaten. Nitrogen intake corrected accordingly.

[220]

NITROGEN BALANCE.—Sliney.

Nitrogen
Taken in.