56 



FOOD INGESTION AND ENERGY TRANSFORMATIONS. 



the heat production 2,057 calories. An examination of the values 

 for the fourth day of fast, December 19 to 20, shows that they are 

 somewhat lower than the basal values obtained from an average of the 

 first 2 days. On all of the 3 food days there was a gradual increase in 

 the carbon-dioxide excretion, oxygen consumption, and heat production 

 as a result of the ingestion of the milk and plasmon, the largest amount 

 being on the last day. Thus, on the 3 days with food there were suc- 

 cessive increases of 4, 37, and 128 grams in the carbon-dioxide pro- 

 duction, 7, 56, and 118 grams in the oxygen consumption, and 47, 166, 

 and 400 calories in the heat production. 



TABLE 7. A. L. L., December 16-23, 1904. (24-hour periods, 7 a. m. to 7 a. m.) 



Milk and plasmon: 1 



Amount, 1,021 grams; nitrogen, 8.57 grams; total energy, 2,577 calories. 

 Fuel value, 2,502 calories; from protein, 9 per cent; from fat, 79 per cent; from 

 carbohydrates, 12 per cent. 



'Expressed as average per day, since the amounts and nutrients were essentially the same each 

 day. 



With this particular experiment, in which an increment was noted 

 on all 3 days with food, the discussion of the results is comparatively 

 simple. Judging by this experiment alone, it is clear that the ingestion 

 of food increased the metabolism over that of the fourth day of 

 fasting, thus bringing the values for the first food day positively 

 above the average for the first 2 days of fasting; there was also a cumu- 

 lative effect, for although exactly the same amount of food was given 

 each day and there was apparently the same amount of muscular 

 activity, the metabolism distinctly increased each day. This increase 

 amounted on the first day to but 2 per cent of the fuel value of the 

 intake, on the second day to 7 per cent, and on the third day to 16 

 per cent. As only a small amount of plasmon was taken and the milk 

 used was a modified milk and contained considerable fat, the actual 



