462 PHYSIOLOGICAL CHEMISTRY. 



teids may gradually decrease with increased quantity of fat. This 

 does not always take place, but on feeding with increased amounts 

 of carbohydrates it does (Vorr). 



The same sparing action on proteids which the neutral fats 

 have occurs, according to J. MUNK, also with the fatty acids, while 

 the second chief constituent of the neutral fats, glycerine, when it 

 is taken in quantities equal to 1-2 grms. per kilo of the body does 

 not seem to have any influence on proteid metabolism (J. MUKK). 



In regard to the metabolism of fat, it has been found that with a 

 constant quantity of proteid in the food the metabolism of fat in- 

 creases with variable amounts of absorbed fats. The following 

 table seems to show this : 



TABLE IX. 

 Food. Fat. 



Meat. Fat. Metabolized. On the Body. 

 500 47 -47 



500 100 66 +34 



500 200 109 +91 



The fat of the body acts like the fat of the food. A body rich 

 in fat decomposes a greater fraction of fat than a lean body, and 

 the same quantity of absorbed fat of the food, which in a fat body 

 is completely decomposed, may in a lean body cause a deposit of 

 fat. If the body takes greater amounts of fat and proteids than it 

 can decompose in the same time, then with increasing amounts of 

 absorbed fats the fraction of the same which is deposited in the 

 body also increases (see Table IX). The greatest deposit of pro- 

 teids and fat occurs after taking medium quantities of both in 

 proper proportion to each other (see below). 



Exchange of Material with a Diet consisting of Proteids and 

 Carbohydrates. That which has been said above in regard to the 

 action of fats on the metabolism of proteids answers essentially also 

 for the carbohydrates. The carbohydrates may also spare the 

 proteids. By the addition of carbohydrates to the food the carnivora 

 not only remains in nitrogenous equilibrium, but the same quantity 

 of meat which in itself is insufficient and which without carbo- 

 hydrates would cause a loss of weight in the body may with the 

 addition of carbohydrates produce a deposit of proteids. The 



