GENERAL THERAPEUTIC MEASURES, 



Food and Feeding. 



In order to comprehend the rationale of feeding in dis- 

 ease it is essential to know something of the principles of 

 feeding in health. A food has been defined as " that which, 

 being innocuous in relation to the tissues, is a digestible, 

 absorbable substance that can be oxidized in the body and 

 decomposed in such a way as to give up to the body the 

 forces it contains." 



A complete food is composed of organic and inor- 

 ganic constituents. The inorganic matters, with the ex- 

 ception of common salt, and rarely phosphate of lime 

 and sodium, are usually present in sufficient quantity in 

 ordinary food. The organic components of vegetable food 

 stuffs are divided into nitrogenous and non-nitrogenous 

 classes. These are analogous to the constituent parts of the 

 animal body into which they are transformed. The greater 

 portion of animal tissue is made up of nitrogenous elements, 

 while the larger part of plants is composed of non-nitrogen- 

 ous material. Among the nitrogenous elements the most 

 important are the proteids. Gluten of flour is an example of 

 a vegetable proteid ; while white of egg, casein of milk, and 

 fibrin of blood represent animal proteids. Fat exists as 

 such in both plants and animals. A single, chemical com- 

 pound, as protein, is known as a nutrient in relation to feed- 

 ing. The nutrients of importance are proteids, fat, and 

 carbohydrates. The first two are common to animal and 

 plant structure ; the latter to plants alone. A complete 

 food contains the three nutrients just mentioned and inor- 

 ganic substances. Carbohydrates include such bodies as 

 sugar, starch, and cellulose, or woody matter of plants. 



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