BASAL METABOLISM. 



57 



amount of nitrogen ingested was not large; hence the increment due to 

 the stimulating action of protein could not be expected to be very great. 

 In addition, it should be pointed out that 79 per cent of the energy 

 came from milk fat. Obviously if the last day of fasting were taken as 

 the base-line, all of the increments would be materially larger. 



The next series of experiments, that with S. A. B., January 7 to 12, 

 1905, included a 4-day fasting experiment, followed by a food experi- 

 ment of only one day, as the subject was unable to continue the diet 

 longer. 1 The results of this latter experiment are given in table 8. 

 The food consisted of the somewhat unusual combination of a modified 

 milk and orange juice, a diet insisted upon by the subject as a SUP- 

 TABLE 8. S. A. B., January 8-12, 1905. (24-hour periods, 7 a. m. to 7 a. m.) 



Milk and orange juice: 



Amount, 1,359 grams; nitrogen, 6.24 grams; total energy, 1,752 calories. 

 Fuel value, 1,698 calories; from protein, 9 per cent; from fat, 73 per cent; 

 from carbohydrates, 18 per cent. 



1 First day not included because of work done on bicycle ergometer. 



posedly advantageous method of breaking a moderately long fast. 

 As on the first day of fasting there was more muscular activity than 

 usual, the values obtained on that day are not suitable for a base-line. 

 The food values are therefore compared with those for the second day 

 of the fast. On comparing the fasting and food values, we find that 

 this experiment differs from that preceding in that here the digestive 

 activity produced no increment in the metabolism, the values for the 

 food day being lower than those for the second day of fast. On the 

 other hand, when the fourth day is used as a base-line, there appears to 

 be an increase in the metabolism after the food. It should be noted 

 in this connection that the amount of energy in the diet from both 

 protein and carbohydrates was small, the total fuel value of the food 

 being only 1,698 calories. The only deduction which can be made 

 from this experiment is that after 4 days of fast, the ingestion of 1,359 

 grams of food of the composition noted was not sufficient to raise the 



'For the detailed results of this series, see Benedict, Carnegie Inst. Wash. Pub. No. 77, 1907, 

 experiments Nos. 71 and 72. 



