128 POPULAR SCIENCE MONTHLY. 



of the subject of human nutrition, practised a certain degree of ab- 

 stinence in the taking of food and attained important economy with, 

 as he believes, great gain in bodily and mental vigor and with marked 

 improvement in his general health. Under his new method of living 

 he finds himself possessed of a peculiar fitness for work of all kinds 

 and with freedom from the ordinary fatigue incidental to extra 

 physical exertion. In using the word abstinence possibly a wrong 

 impression is given, for the habits of life now followed have resulted 

 in the disappearance of the ordinary craving for food. In other 

 words, the gentleman in question fully satisfies his appetite, but no 

 longer desires the amount of food consumed by most individuals. 



For a period of thirteen days, in January, he was under ob- 

 servation in the writer's laboratory, his excretions being analyzed 

 daily with a view to ascertaining the exact amount of proteid con- 

 sumed. The results showed that the average daily amount of pro- 

 teid metabolized was 41.25 grams, the body- weight (165 pounds) 

 remaining practically constant. Especially noteworthy also was the 

 very complete utilization of the proteid food during this period of 

 observation. It will be observed here that the daily amount of pro- 

 teid food taken was less than one half that of the minimum Voit 

 standard, and it should also be mentioned that this apparent deficiency 

 in proteid food was not made good by any large consumption of fats 

 or carbohydrates. Further, there was no restriction in diet. On the 

 contrary, there was perfect freedom of choice, and the instructions 

 given were to follow his usual dietetic habits. Analysis of the excre- 

 tions showed an output of nitrogen equal to the breaking down of 

 41.25 grams of proteid per day, as an average, the extremes being 

 33.06 grams and 47.05 grams of proteid. 



In February, a more thorough series of observations was made, 

 involving a careful analysis of the daily diet, together with analysis 

 of the excreta, so that not alone the proteid consumption might be 

 ascertained, but likevsdse the total intake of fats and carbohydrates. 

 The diet consumed was quite simple, and consisted merely of a pre- 

 pared cereal food, milk and maple sugar. This diet was taken twice 

 a day for seven days, and was selected by the subject as giving sufii- 

 cient variety for his needs and quite in accord with his taste. No 

 attempt was made to conform to any given standard of quantity, but 

 the subject took each day such amounts of the above foods as his 

 appetite craved. Each portion taken, however, was carefully weighed 

 in the laboratory, the chemical composition of the food determined, 

 and the fuel value calculated by the usual methods. 



The following table gives the daily intake of proteids, fats and 

 carbohydrates for six days, together with the calculated fuel value, and 

 also the nitrogen intake, together with the nitrogen output through 

 the excreta. Many other data were obtained showing diminished 



