280 



FOODS AND DIETARIES 



U S Otfttmtnt ot Agriculture Prepared by 



Oll.Cf o> Eioer.meni Stlt.ons C. f UNGWORTHY 



A. C. True: Director Expert in Charge ot Nutrition Investigations 



COMPOSITION OF FOOD MATERIALS. 



WHOLE MILK 



SKIM MILK 



FlXl MUK: l65uiOl[SPfPPOiW> 



BUTTERMILK 



Proteir>:3.0 Fat: I8.5-, J 

 Ash:0 5 



Carbohydrates:4.8 



i 



MLUC: l60cU. IH>MD Fun VUM: 880 OLOI 



The Relation of Environment to Diet. We are all aware of the 

 fact that the body seems to crave more food in winter than in 



summer. The temperature of 

 the body is maintained at 98.6 

 in winter as in summer, but 

 much more heat is lost from the 

 body in cold weather. Hence 

 feeding in winter should be for 

 the purpose of maintaining our 

 fuel supply. We need heat- 

 producing food, and we need 

 more food in winter than in 

 summer. We may use carbo 

 hydrates for this purpose, as 

 they are economical and diges 

 tible. The inhabitants of cold 

 countries get their heat-releasing 

 foods largely from fats. In 

 tropical countries and in hot 

 weather little protein should 

 be eaten and a considerable 

 amount of fresh fruit used. 



The Relation of Age to Diet. As we will see a little later, age 

 is a factor not only in determining the kind but the amount of 

 food to be used. Young children require far less food than do 

 those of older growth or adults. The body constantly increases 

 in weight until young manhood, or womanhood, then its weight 

 remains nearly stationary, varying with health or illness. It is 

 evident that food in adults simply repairs the waste of cells and 

 is used to supply energy. Elderly people need much less protein 

 than do younger persons. But inasmuch as the amount of food 

 to be taken into the body should be in proportion to the body 

 weight, it is also evident that growing children do not, as is popu 

 larly supposed, need as much food as grown-ups. 



The Relation of Sex to Diet. As a rule boys need more food 

 than girls, and men than women. This seems to be due to, first, 

 the more active muscular life of the man and, secondly, to the 



The composition of milk. 



