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 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 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.