12 HAROLD L. HIGGINS 



main source of energy. In practically every fast, one finds from eighty 

 to ninety per cent of the calories come from fat, while the remaining ten 

 to twenty per cent come from protein. But as body protein exists as flesh 

 containing eighty per cent water, and as the energy of a gram of protein 

 is only four-ninths of that of fat, the net result is that about two grams 

 of body flesh is lost for every gram of body fat. This ratio persists until 

 just before death from fasting. Then, suddenly, one finds a big increase 

 in the protein metabolism as indicated by the nitrogen excretion in the 

 urine. This is spoken of as the premortal nitrogen rise. 



The explanation of this premortal rise has been believed to be that 

 the fat of the body has been completely used up and therefore protein has 

 to bear the whole brunt of the energy production in the body; thus the 

 nitrogen output, in the urine rises, the cells themselves die from too much 

 depletion of their nitrogen content, and general death follows. The 

 above explanation is not wholly correct, for analysis of the bodies of some 

 animals that have had this premortal nitrogen rise and died, have shown 

 still a small amount of fatty tissue present (Bidder and Schmidt, 1852). 

 The theory has been advanced that an autointoxication lowers the destruc- 

 tive ability of the cells for fat and retards the solution of fats from the 

 great fat depots (Tigerstedt, 1906). The general cell destruction thus 

 seems to take place before the fat is wholly utilized (Schulz(a), 1897). 

 So long as the fat produces approximately eighty per cent of the body 

 heat in a fast, the organism shows no immediate danger of death. After 

 the premortal rise of nitrogen has been observed, death has been forestalled 

 by subcutaneous injections of oil (Koll, 1887) or sugar (Kaufman, 1901). 



Absolute fat starvation leads to disturbances characterized by gastric 

 and intestinal disorders, loss of appetite and eventually perhaps metabolic 

 disturbances from want of vitamines, which are in the fat of the diet. 

 Fat is essential for the palatability of _the diet. 



Protein Metabolism 



The protein katabolized in fasting comes, in a large part, from the 

 less vital organs and from the muscles. Only a few of the cells which 

 furnish this protein are destroyed. Thus histological examination shows 

 the muscle cells to be smaller and apparently but little decreased in num- 

 ber after fasting. The protoplasm is used up, but the nucleus is still 

 essentially intact and the cell lives. This seems quite in keeping with 

 the findings that long fasts seem to produce no permanently harmful effects 

 upon the individual. The professional fasters seem quite as healthy as 

 ever a few weeks after the fast is concluded. There is a record of a dog 

 which fasted one hundred and seventeen days and then, after spending 

 the summer on a farm, was in even better shape than before the fast, and 



