14 HAKOLD L. HIGGINS 



(Landergren, 1903). This is shown in the table for the three days 

 following the fast, when the diet was largely carbohydrate. 



In the first days of fasting, so long as there is an appreciable amount 

 of glycogen being burned, the protein destruction is not so large as later. 

 The nitrogen excretion then reaches its maximum and gradually falls, the 

 fall being more or less parallel with the fall in heat production, for 

 throughout the fast the protein furnishes about fifteen to twenty per cent 

 of the energy. 



Urea, which normally constitutes about eighty-seven and a half per- 

 cent of the total nitrogen of the urine, fell to about seventy per cent after 

 the glycogen of the body had been depleted, and remained low for the 

 duration of the fast. As the urea fell the ammonia rose, the sum of the 

 two equaling in fasting about ninety per cent as compared with a normal 

 of ninety-one or ninety-two per cent. 



The ammonia nitrogen in fasting consisted of about fifteen to twenty 

 per cent of the total nitrogen in the urine. The relatively high percentage 

 of ammonia in the urine is doubtless to be explained on the basis of a rela- 

 tive acidosis. The blood in starvation has a slightly diminished alkali 

 reserve, the alveolar air is lowered correspondingly, and there are acetone 

 bodies being constantly formed in the body. The higher ammonia in the 

 fasting urine is one of the body's means of defense against acidosis. 



The uric acid excretion was low the first few days of the fast; this 

 low figure may be associated with the utilization of glycogen; then the 

 uric acid rose in amount and in general remained constant throughout the 

 fast The significance of the uric acid in fasting is admittedly unknown. 

 It is lower than endogenous uric acid in feeding, and this has been ascribed 

 to absence of glandular activity in fasting. 



The total creatinine excretion (i. e., creatine and creatinine) in the 

 urine also is apparently subject to no great variation from day to day. 

 The tendency is to regard the amount of creatinine in the "urine propor- 

 tional to the amount of active protoplasmic tissues (Folin and Denis (e), 

 1913-14; Palmer, Means and Gamble, 1914). It is interesting to note that 

 the creatinine excretion in the urine fell somewhat proportionally to the 

 body weight. The total creatinine consists of creatinine and creatine. It 

 has been the general opinion that, whereas creatine did not appear in the 

 urine normally, if none were taken by mouth, it did appear during starva- 

 tion. Considerable doubt has been thrown upon this opinion by recent 

 study in the methods of analysis and much of the previous work on the 

 creatine and creatinine portions of the total creatinine fraction of the urine 

 (Graham and Poulton(fe), 1914). More recent work tends to show that 

 there is some creatine in the urine in fasting, although not so much as had 

 previously been thought to be the case (Zeman and Howe, 1915). 



The sulphur in urine comes from the protein and in fasting bears a 



