COMPOSITION OF FOODS 307 



conditions render necessary, or the producer pleases, to 

 place on his goods. 



It is true, these factors must be considered. But 

 first we must determine the kind of food which will 

 supply the materials which our bodies need. The 

 amount of protein needed will vary with the amount 

 of manual labor we do, the amount of fat and carbo- 

 hydrate with the energy used, and also with the tem- 

 perature. The highest priced foods are not always the 

 most nutritious. Neither is it always economy to buy 

 the cheapest foods. The problem is how to buy the 

 largest amount of nutritious food for the least money. 



Adulteration. The purchaser must also consider the 

 relative purity of foods. This is especially necessary 

 in different brands of canned goods. Many of them 

 contain adulterants or preservatives which are danger- 

 ous to the health. Legislative measures are now being 

 taken to protect the public against adulterated foods. 

 A national law, commonly known as "The Pure Food 

 Law," was passed in 1906 for the prevention of adulter- 

 ation and misbranding of foods or drugs. This 

 stimulated further state legislation. Now nearly every 

 state has a general food law and is making an attempt 

 to enforce it. 



Cooking 1 . Some foods, like, fruits, milk, and nuts, 

 are eaten without being cooked. The great majority, 

 however, are cooked. As a result of cooking, meats 

 and vegetables are more easily digested and are made 

 more palatable. 



