THE HYGIENE OF NUTRITION 221 



tainly originated during the lifetime of the animal through 

 the breaking down of its proteins, and were destined for 

 ultimate excretion, either unchanged or after some altera- 

 tion. It is hard to escape the conclusion that our pleasure 

 in the taste of meat is due to compounds nearly akin to 

 those of the urine. 



Furthermore, it is plain that the opponents of meat are 

 correct in making the point that when we receive these ex- 

 tractives we are simply adding to the duties of our own kid- 

 neys. When we eat 50 grams of protein in beans we have 

 later to excrete about 8 grams of nitrogen in urea and other 

 forms. When we eat 50 grams of protein in beefsteak we 

 must subsequently excrete the same quantity of nitrogen 

 plus that of the extractive bodies. The addition is not a 

 large one, but it is partly in the form of uric acid and per- 

 haps other bodies less tractable than urea. The advisa- 

 bility of limiting meat in rheumatism and related conditions 

 has long been recognized. 



While the extractives may be held to account for some of 

 the possible ill effects of meat, they are also the source of its 

 especial virtue. Palat ability itself is of great hygienic 

 worth, and these substances confer qualities which for 

 most people cannot be equaled apart from meat. The 

 promotion of gastric secretion in the normal subject and 

 its establishment in the invalid are most surely secured by 

 means of these same extractives. Aside from their favor- 

 able influence upon the stomach, they are probably mild 

 stimulants in the same sense in which coffee and tea can 

 be called so. 



Some kinds of meat are well known to occasion indiges- 

 tion. Pork and veal are particularly feared. While we 

 may not know the reason why these foods so often disagree 

 with people, it seems probable that texture is an important 

 consideration. In both these meats the fiber is fine, and 

 fat is intimately mingled with the lean. A close blending 

 of fat with nitrogenous matter appears to give a fabric 

 which it is hard to digest. The same principle is illus- 

 trated by fat-soaked fried foods. Under the cover of the 



