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. 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