Although the first 5 values for the urinary nitrogen in table 44, which are also shown in table 41, may be taken to indicate the normal nitrogen output for the group of 12 men when they were on unrestricted diet, the evidence is not absolutely clear, for it can be seen from table 40 that although the men were supposed to be eating in a perfectly-normal manner, as a matter of fact they took absolutely the same amount of nitrogen on two of the three days recorded and nearly the same on the third day. Hence, we do not deal here with a true uncontrolled diet. The data are therefore somewhat defective in indicating the probable normal urinary excretion of the undergraduates of this college.

Immediately prior to placing Squad B upon restricted diet in January, urine was collected from these men for a period usually varying from 16 1/2 to 27 hours, and the nitrogen excretion computed therefrom on the 24-hour basis. These data are given in the lower portion of table 45. The average value for the entire group, calculated on the 24-hour basis, was 13.14 grams. The average value for Squad A during the last 2 days in September, was 11.48 grams; for the first 3 days in October it was 12.88 grams. (See table 41.) The latter average is practically the same as that found in the fragmentary data with Squad B, i. e., 13.14 grams.

At the conclusion of our experiment at Springfield it became evident that we should have further data regarding the probable normal urinary excretion. It was observed by all of us that the college men were well fed, apparently enjoyed their meals, had a great deal of physical exercise and were very busy men. In spite of the general tendency towards conservation of wheat products, it appeared not unlikely that these men might normally eat considerable quantities of protein. This was further emphasized to our minds by the fact that on the days of uncontrolled diet practically all of our subjects took rather liberal amounts of protein. Consequently Professor Elmer Berry was sufficiently interested to arrange with another group of 12 men, none of whom had served on either squad, for the daily collection of their entire urine for 4 days, i. e., February 11 to 15, inclusive. These urines were sent to the Nutrition Laboratory and there analyzed. The results are given in the upper part of table 45, and show that the average for these 12 men in this time was 13.97 grams, a little more than that calculated for Squad B and approximately 1 gram more than was found for Squad A during the first 3 days in October. It is somewhat questionable, of course, to assume that exactly the same dietetic habits would obtain, so far as protein intake is concerned, in the middle of February as in the first week in October. Nevertheless, it is highly probable that the average nitrogen excretion of these men is not far from 13 grams per day. Consequently we may rightly infer from the examination of the data in table 44 that Squad A, while on the reduced diet, had a nitrogen excretion averaging not far from 10.5 to 11 grams, and hence was on a slightly lower nitrogen output per day than was the regular undergraduate body of the Y. M. C. A. College.

Table 45. - Nitrogen Excretion Of International Y. M. C. A. College Students During Periods With Normal Diet

Statistics Of Urine For Squad B On Reduced Diet

Since the purpose of placing Squad B upon restricted diet was somewhat different from that for Squad A and the reduction in diet was very much greater, the statistics of urine for this squad are not given special treatment in this discussion. The values for the nitrogen per 24 hours in urine and the corresponding amounts of nitrogen in the food are given in the nitrogen balance tables 59 to 70 in a subsequent section. It is only necessary to point out at this time that an inspection of these tables shows that in spite of the great curtailment of nitrogen intake of nearly one-half, the average nitrogen output remained with singular persistency over 9.5 grams, there being but one exception. Kim, with the relatively low average body-weight of 61 kilograms, showed an average nitrogen excretion of 9.2 grams. Since all these men had practically the same nitrogen intake of not far from 8 grams (for no fluctuation in the nitrogen intake appeared in this short period which was at all comparable to the variations in nitrogen intake found with Squad A) the consistency and uniformity in nitrogen excretion are all the more remarkable and point immediately toward a very considerable nitrogen loss, which will be subsequently discussed. The wholly remarkable consistency of nitrogen excretion in the urine, irrespective of the nitrogen ingested, explains largely the singularly anomalous fact that the nitrogen excretion of the subjects in Squad A on the Mondays following the free Sundays was not materially affected by the relatively large nitrogen intake on these days. The two subjects in Squad A, Gul and Pec, who collected the urine during the Christmas recess, showed relatively little change in the nitrogen output as compared with their probable nitrogen intake. See tables 51a and 55a, pages 325 and 336. The uniformity of nitrogen excretion with extraordinarily large changes in nitrogen intake in the food is a point worthy of special emphasis.