CHAPTER XIV. 

 FOODS AND COOKING. 



Necessity of Food. Thus far we have been studying 

 processes by which the body's weight is reduced. We 

 have studied the oxidation in the tissues and the removal 

 of the wastes. Unless the tissues receive a supply of new 

 material, the heat and energy of the body cannot long be 

 kept up. 



Food Defined. Foods are substances that build tissues 

 or produce energy without injuring any organ or function 

 of the body. Certain substances that -do not become part 

 of any tissues, nor in themselves produce energy, are use- 

 ful in aiding the processes going on in the body. These 

 may be called accessory foods, e.g. condiments, such as 

 pepper. 



Foods and Foodstuffs. Most of our articles of food 

 consist of two or more different kinds of materials. For 

 instance, milk consists (i) chiefly of water; and in it are 

 (2) the substance that makes cheese (casein); (3) cream, 

 from which we get butter (fat); (4) sugar, which gives 

 milk a sweet taste; (5) salts, such as common salt, lime 

 salts, etc. These different materials are foodstuffs. We 

 have many kinds of foods, but few foodstuffs, which we 

 find occurring over and over again, in various forms, in 

 the numerous things we eat. 



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