FOOD 2O I 



taken in excess, part of it will be wasted. If the amount 

 of one foodstuff absorbed be too little, the man must con- 

 sume part of his body substances, and will lose in weight. 

 In pure albumin, such as the white of egg, the proportion of 

 nitrogen to carbon is I to 3 J. Since the proportion needed 

 in his body is I to 15, if he eats enough white of egg to 

 get just enough nitrogen, he would only get about one 

 fourth as much carbon as he requires ; for the body needs 

 15 times as much carbon as nitrogen instead of 3| times as 

 much. But if he were to eat enough of egg white to get 

 the carbon required, he would eat four times as much 

 nitrogen as the body would use. If he subsisted on lean 

 meat, he would eat four pounds a day to gain sufficient car- 

 bon, while three fourths of a pound would have supplied 

 sufficient nitrogen. 



355. A dog could readily live on lean meat alone. If a 

 man attempted to do so, the kidneys would have to excrete 

 the larger part of the nitrogen unused, and would probably 

 become diseased from overwork, if, indeed, the meat did 

 not become nauseous to the palate and stop the experi- 

 ment. Yet, so flexible is the human system, if only 

 plenty of fresh air and exercise are taken, that the 

 Gauchos (a tribe of Indians on the Pampas of South 

 America) live upon dried beef alone. But the habit is a 

 strain upon the organs, and must have been acquired 

 gradually. They are a very short-lived tribe. 



356. Proteid contains carbon as well as the carbona- 

 ceous foods, but not so much ; and it is found that proteid 

 and carbonaceous food in the proportion of I to 4 gives 

 the needed proportion of nitrogen to carbon (i to 15). 



357. How the Proportion of One to Four is attained. - 

 Since fat, starch, and sugar do not contain nitrogen, it is 

 impossible to live upon them alone. A dog fed only upon 

 carbonaceous food, died in a few days. Since these foods 

 contain plenty of carbon, it is obvious that by mixing them 



