142 METABOLISM AND NUTRITION 



a man strong enough to do nine to ten hours* work every day heavier than 

 that of a tailor and lighter than that of a blacksmith the work for example 

 of a mason, a carpenter, or a joiner. Moderate work so defined corresponds 

 fairly well to the amount done by most manual laborers, and comes nearest 

 to Group III in our classification. 



Voit's ration for the moderate worker is: 118 g. proteid, 56 g. fat, and 

 500 g. carbohydrate = 3,055 Cal. gross or 2,749 Cal. net. 



While it has been generally admitted that the absolute supply of energy in 

 this ration corresponds well with the actual requirements and is estimated rather 

 too low than too high, it has been remarked by many that the amount of pro- 

 teid is too high and that a moderate worker can get along perfectly with less 

 proteid. Munk for example proposes 110 g. proteid instead of 118 g. Now it 

 is not a matter of great moment whether the diet contain 110 or 118 g. proteid. 

 The rations which we have brought together for our Group III contain on the 

 average 130 g. with 113 and 151 g. as the extremes. From Atwater's results we 

 have for the same group 103 g. with 52 and 152 g. as the extremes. This is not 

 the place to discuss the grounds which have been taken for a reduction of pro- 

 teid in the ration. In the opinion of the author these grounds are by no means 

 sufficient for the purpose intended, hence the best thing to do is to choose for a 

 normal ration on containing not less than 118 g. proteid, even is many observa- 

 tions do show that a " moderate worker " can get along with less. 



[Chittenden's recent experiments on several groups of men of different de- 

 grees of muscular and mental activity (university professors, college athletes, 

 and United States soldiers) indicate strongly that Voit's proteid ration is ex- 

 cessive. He found that without exception these persons (numbering twenty-six 

 in all) were able to maintain their physical and mental vigor for periods of 

 from five to nine months on an average of 56 grams of proteid per day. These 

 results accord with Folin's theory of metabolism (cf. page 137), which looks 

 upon a large part of the proteid ingested in the average diet as so much waste 

 material to be removed at once from the circulation by the liver. ED.] 



Voit's motive in dividing the nonnitrogenous foodstuffs for a moderate 

 worker between fat and carbohydrates as he did, was to make the diet as 

 inexpensive as possible. He takes, therefore, as much carbohydrate as in his 

 opinion the intestine can digest easily i. e., 500 g. The remainder of the 

 energy required he takes from fat. 



Of course it would not be correct to regard 500 g. as a real maximum of 

 carbohydrates and Voit does not. The intestine can manage greater quanti- 

 ties; but this alone is no reason for increasing the carbohydrate at the expense 

 of fat. Experience has shown with perfect clearness that the human body has 

 a very pronounced, if not always a perfectly intelligible, need for fat; so that 

 the quantity in Voit's ration (56 g.) ought probably to be regarded as the 

 minimum for the diet of a moderate 'worker (cf. tables on page 141). 



When the amount of work to be done is greater than that of a moderate 

 worker, experience teaches us that both proteid and N-free substances are 

 eaten in greater quantities, but the supply of proteid is not increased as much 

 as that of the N-free substances. According to Voit, soldiers in field maneu- 



