372 Influence of Inanition on Metabolism. 



that the proportion of protein, when compared to that of fat, may have been no 

 greater in the later than in the earlier experiments. The increase in water 

 content of the body, however, may well lower the proportion of total protein 

 in the body even with the material gain observed in the long nitrogen 

 metabolism experiments. 



Although the evidence is insufficient for drawing any definite conclusions, 

 the results obtained imply that after the first fasting day the supply of reserve 

 protein in the body has little, if any, effect on the subsequent excretion of 

 nitrogen. Further experiments in which the partition of the nitrogen is more 

 carefully studied are needed. 1 



Excretion of nitrogen in different periods of the day. The samples of urine 

 for the four periods of each day were separately analyzed during a portion of the 

 series of experiments in the effort to obtain information concerning the 

 distribution of nitrogen excretion. 



These data are presented in table 198, in which the excretion for the two 

 6-hour day periods and the 12-hour night period are given. In this table the 

 results for the periods from 7 p. m. to 11 p. m., and 11 p. m. to 7 a. m. are 

 combined. 



The proportions of the total nitrogen excreted during the day period and 

 the night period have likewise been computed and the percentages expressed 

 in the table. 



The data in the table, which includes all the fasting experiments in which 

 determinations by periods were made, show that during the period from 7 a. m. 

 to 7 p. m. the per cent of total nitrogen may vary from 47.5 per cent, as on 

 the second day of experiment No. 89, to 60.5 per cent, as on the first day of 

 experiment No. 75. On the average 51.9 per cent of the total nitrogen is 

 excreted during the day period. 



There is a general tendency for the per cent of nitrogen excreted during the 

 day period to increase perceptibly as the fast progresses in experiments Nos. 69 

 and 73. On the contrary, in experiment No. 75, the highest percentage is on 

 the first, the lowest on the third day. 



The proportions of nitrogen eliminated during the periods from 7 a. m. to 

 1 p. m. and 1 p. m. to 7 p. m. have not been shown separately in the table, 

 but in general the larger excretion takes place during the period from 7 a. m. to 

 1 p. m., although the average for all the experiments is only about 2 per cent 

 larger. Thus 51 per cent of the total nitrogen excreted during the first 12 hours 

 of the day appears in the urine of the six hours from 7 a. m. to 1 p. m. 

 A few noticeable exceptions are observed especially in the second day of experi- 

 ment No. 59, both days of experiment No. 68 and in the second day of 

 experiment No. 89. 



1 Folin's result on a fasting (see p. 364) man are of interest in that the subject 

 had subsisted on a low nitrogen diet for some days before the fast began. 



