934 METABOLISM. 



is about four-fifths that of a laboring man, and we may consider the 

 following as a daily diet with moderate work : 



Proteins. Fat. Carbohydrates. Calories. 



For women 94 grams 45 grams 400 grams 2240 



The proportion of fat to carbohydrates is here as 1:8-9. Such a 

 proportion often occurs in the. food of the poorer classes who chiefly live 

 upon the cheap and voluminous vegetable food, while this ratio in the 

 food of wealthier persons is 1 :3-4. It would be desirable if in the above 

 rations the fat were increased at the expense of the carbohydrates, but 

 unfortunately on account of the high price of fat such a modification 

 cannot always be made. 



In examining the above figures for the daily rations it must not 

 be forgotten that those for the various foodstuffs are gross results. 

 They consequently represent the quantity of those which must be taken 

 in, and not those which are really absorbed. The figures for the calories 

 are, on the contrary, net results. 



The various foods are, as is well known, not equally digested and 

 absorbed, and in general the vegetable foods are less completely consumed 

 than animal foods. This is especially true of the proteins. When, 

 therefore, VOIT, as above stated, calculates the daily quantity of pro- 

 teins needed by a laborer as 118 grams, he starts with the supposition 

 that the diet is a mixed animal and vegetable one, and also that of the 

 above 118 grams about 105 grams are absorbed. The results obtained 

 by PFLUGER and his pupils BOHLAND and BLEIBTREU 1 on the extent of 

 the metabolism of proteins in man with an optional and sufficient diet 

 correspond well with the above figures, when the unequal weight of body 

 of the various persons experimented upon is sufficiently considered. 



As a rule, the more exclusively a vegetable food is employed, the 

 smaller is the quantity of proteins in it. The strictly vegetable diet 

 of certain people, as that of the Japanese and of the so-called vegeta- 

 rians, is therefore a proof that, if the quantity of food be sufficient, a 

 person may exist on considerably smaller quantities of proteins than 

 VOIT suggests. It follows from the investigations of HIRSCHFELD, KUMA- 

 GAWA and KLEMPERER, SIVEN, and others (see pages 903, 915) that an 

 almost complete or indeed a complete nitrogenous equilibrium may be 

 attained by the sufficient administration of non-nitrogeneous nutritive 

 bodies with relatively very small quantities of proteins. 



If we bear in mind that the food of people of different countries 

 varies greatly, and that the individual also takes essentially different 

 nourishment according to the external conditions of living and the influence 

 of climate, it is not remarkable that a person accustomed to a mixed 



1 Bohland, Pfluger's Arch., 36; Bleibtreu, ibid., 38. 



