The Farm Table, 



659 



" always weighing and considering '" and has " even been known to change 

 his mind," but we can no longer afiford to live without such help. Science, 

 building upon the experience of the ages, is giving us the means of solv- 

 ing many a difficult problem, and is making possible healthier, happier 

 life than was within our reach before. 



I. Standard Dietaries. 



The most difficult question in regard to the selection of food is how 

 to choose the amount of different kinds necessary to supply our daily 

 needs, and how to vary this for different conditions, such as different ages 

 and dift'erent amounts of work. To help us in this the " standard dieta- 

 ries " have been given. These dietaries have sometimes been called experi- 

 mental, and sometimes statistical, according to the methods used in formu- 

 lating them. An experimental dietary is the result of careful observations 

 of the effect of different proportions of food nutrients upon an individual. 

 The statistical dietary is the outcome of the study of the actual ration of 

 large numbers of people. Each of these has its drawbacks. In the first 

 case it is difficult to decide how far the result is due to individual pecu- 

 liarities, and a large number of experiments must be tried. In the second 

 case it is difficult to determine whether some variation in the diet might 

 not produce better results. But from a careful comparison of dietaries 

 made up in these two ways certain standards have been determined upon. 



The standard dietaries for Americans are given us as follows : 



Calories. 



Woman with light exercise. 

 Man with light exercise. . . . 



Man at moderate work 



Man at hard work 



2 , .300 

 2,815 

 3,520 

 4,060 



A man of moderate work therefore would require about 4^ ozs. of 

 proteid, 4^ of fat, and nearly a pound of carbohydrate daily. 



The diet of children varies with their age. It differs from that of 

 the adult in being less in amount, and with different proportions of the 

 food elements. For example, the growing child needs a much larger 

 proportion of proteid in its food than does the grown person. The varia- 

 tion in diet at different ages has been illustrated by the chart on the first 

 page (Fig. 171). 



This chart agrees with the experience of the mother who has brought 

 up several children. The amount eaten by the little child increases rapidly 

 till he is about four years old, then very slowly till he is nine or ten, then 

 it takes a sudden jump till it seems difficult to provide enough food tQ 

 satisfy it, If he can be induced to masticate his food properly the mother 



