CHAPTER XXV 

 THE REQUISITES OF THE DIET 



In this chapter we shall include a summary and 

 restatement of much that has gone before. We shall 

 also have new material to add. If we begin the attempt 

 to define an adequate diet we shall probably think first 

 of the calorific requirement. If the specific case is 

 that of a student taking a limited amount of exercise 

 we may fix upon 2500 Calories as a fair standard. We 

 must think next of the protein allowance. 



The amount mentioned in the last chapter, 75 grams, 

 is about what one is likely to take. The older state- 

 ment that the average protein ration is 100 grams a 

 day is not confirmed by recent reports. The protein 

 should be from several sources. The unequal nutritive 

 virtues of different proteins should be recalled. Pro- 

 teins for growth may have ceased to be called for, but 

 proteins for maintenance must still be supplied. 



The non-protein part of the diet will be composed of 

 carbohydrates and fats in proportions which may be 

 widely varied. The usual tendency is to take both, but to 

 make the greater use of carbohydrates. The Esquimaux 

 exhibit the possibility of living on proteins and fats with 

 a minimum of starch and sugar, but this course is forced 

 upon them by necessity and does not indicate that it 

 would be chosen instinctively. Their protein consump- 

 tion is very great and we must remember that surplus 

 protein becomes a source of sugar in the system. Since 

 sugar must be at hand when fat is to be oxidized we may 

 suppose that carnivorous men and animals are pro- 

 tected against acidosis because they take more protein 

 than they appear to need. 



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