METABOLISM. 593 



the organism. It imposes a needless labor on the excretory organs. 

 Moderation in the taking of proteid foods means a great saving in the 

 wear and tear of the body machinery, especially the kidneys and liver, 

 and a lessened production of uric acid. 



A vegetable dietary is not desirable, for the vegetable proteids 

 in decomposition differ much more in amido-acids from the serum 

 proteids than the animal food proteids. Hence a mixed diet, having 

 proteids of varying composition, is needed, for the absence of amido- 

 acids in a food proteid can be replaced by another food proteid having 

 a comparative excess of the same amido-acids. 



Benedict concludes that Chittenden's permanent restrictions of 

 proteid ingested is decidedly disadvantageous and not without possible 

 danger. Magnus Levy does not believe that the products of nitrog- 

 enous decomposition are injurious to a healthy man, or that the toxines 

 formed in the intestinal canal from an excessive proteid diet are so 

 dangerous as they are held to be. In cases of disease of the liver or 

 kidneys or nervous system, the excess of proteid may be injurious. 



Tigerstedt 3 states that a man can perform work and be in nitrogen 

 equilibrium on a less quantity of proteid than held necessary by Voit. 

 But it does not follow from these experiments that proteid should be 

 diminished. He holds that the diet should contain a sufficient quantity 

 of proteid. 



Eubner believes that meat is the best proteid for the masses. He 

 considers that for a person who worked for an average number of hours 

 daily, the amount of albumin should be 131 grams, whilst 118 grams 

 must be regarded as the minimum. The excess over the amount 

 necessary in the laboratory experiment serves partly as a safety valve 

 and partly to cover the needs of heavier work. 4 



Forster also states that fats could not be utilized to a full extent 

 as long as the body was kept on a minimum of proteid. Animals which 

 were underfed for a considerable period could not always be refattened. 

 He also noted the diminished production of agglutinins during under- 

 feeding. 5 



Leathes states "the food of an infant in the second half of the 

 first year is commonly and normally about two pints of milk. Even 

 taking this to contain only 1.5 per cent, of proteids, that gives 17 

 grams daily, or 2 grams per kilogram, and this estimate, which is 



8 Untersuchungen fiber die Ernahrung der Landvolkerung in Finnland 

 von Sigfrid SundstrCm, 1908. 



4 British Med. Jour., p. 1077, 1907. 



5 British Med, Jour., p. 1077, 1907, 



