STARVATION 97 



Starvation is characterized by a slow but steady fall in the output 

 of nitrogen. The amount of the nitrogenous output in the early days, 

 as Voit showed years ago, is directly proportional to the amount of 

 the previous nitrogenous intake. A uniform output of nitrogen is 

 practically always reached by the seventh day of the fast, irrespective 

 of the nature or amount of the food taken before the fast. In practi- 

 cally every experiment the output of nitrogen is lower on the first day, 

 or two, than during the two or three subsequent days. This is almost 

 certainly due to the body utilizing its stores of free carbohydrate at 

 this period, as Prauznitz (334) in a long series of short experiments 

 on students has clearly demonstrated. Benedict's work supports such 

 an interpretation. 



The main interest, however, in these starvation studies, when the 

 organism is living on a purely endogenous supply of protein, is not 

 in the total nitrogen output but in the partition of the nitrogenous con- 

 stituents. 



The Output of Urea and Ammonia. 



Urea gradually falls both in relative and absolute amount. The 

 same result has been observed by Folin and others when a subject is 

 put upon a diet practically nitrogen-free. In the case of Beaute, 

 during the fasting period the urea output fell to 71 per cent, of the 

 total nitrogen. Hawk (173) in his subjects found the lowest percent- 

 age fall in the output to be 75-8. E. and O. Freund observed on the 

 twentieth day a much lower percentage output, viz. 56 per cent. Now it 

 has been shown by Von Schroeder and many others that the main 

 source of the urea is the ammonia, which is formed in the body either 

 from the deaminization of part of the ingested amino acids, or from some 

 other metabolic process taking place both in hunger and feeding. It 

 is also a well-known fact that one of the symptoms of starvation is 

 acidosis, as Brugsch (77), in his investigations of Succi, and also 

 Bonninger and Mohr (66) have very clearly demonstrated. This 

 acidosis is due presumably to the imperfect combustion of fat ; .under 

 these circumstances, as one of the protective mechanisms of the 

 body, the ammonia formed is used for the neutralization of the acids. 

 The fall in the urea output is accordingly accompanied by a well- 

 marked rise in the output of ammonia. In my investigation, the per- 

 centage output of ammonia in relation to the total nitrogen rose from 

 3 'i 6 per cent, on the last day of feeding to a maximum of 14-88 per 



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