96 



METABOLISM AND NUTRITION 



suddenly. The body weight very gradually declines. The average daily loss in 

 the first five to ten days of long fasting periods endured by men, has been found 

 to be 1.0-1.5 per cent of the original weight. 



During fasting a mass consisting of worn-out epithelial cells and residues 

 of the digestive fluids accumulates in the intestine, which either during the fast 

 or after it is broken is evacuated as fasces (cf. Chapter VII). From observations 

 on fasting men, the daily quantity of fresh faeces is estimated at 9.5-22.0 g., of 

 dry faeces at 2-3.8 g. They contain 0.113-0.316 g. of nitrogen, 0.44-1.35 g. 

 of ether extract and 0.25-0.48 g. of ash. Microscopic examination of faeces 

 reveals numerous fine, needle-shaped crystals of the fatty acids embedded within 

 a finely granular, amorphous ground substance, but no true formed constituents. 



B. CHARACTER OF THE METABOLISM IN FASTING 



In fasting the total metabolism falls gradually from the first day onward. 

 Estimated per kg. of body weight, however, the daily decline is only rela- 

 tively small and remains for a long time at about the minimum reached at 

 the beginning of the fasting period. As proof of this statement, we give here 

 the results of a five-day fasting experiment on a man. 



As is customary in fasting experiments, we have assumed that the total 

 quantity of carbon from nonnitrogenous substances comes from fat. But the 

 body contains at the beginning of the fast a certain quantity of glycogen, 

 whose heat value calculated per g. of carbon is less than that of fat. This 

 glycogen disappears for the most part during the first day of starvation and 

 a part of the carbon reckoned as fat doubtless has its origin in this glycogen. 

 Our figures for the total metabolism, during the first two fasting days at 

 least, are, for this reason, too large; and hence it is possible that the body 

 reaches its minimum metabolism on the first or second day of fasting. 



To enter further into the processes of metabolism in fasting it will be 

 necessary for us to discuss the decomposition of proteid and fat more fully. 

 Nothing further can be said at present concerning the share of carbohydrates 

 stored in the body in these decompositions, and in any case it must be regarded 

 as unimportant in comparison with that of fat. 



Experiments show that with well-nourished animals, having a plentiful 

 deposit of fat in their bodies, the destruction of proteid gradually declines 

 day by day until death; whereas with poorly nourished, lean animals after a 



