124 APPLIED PHYSIOLOGY 



trate. Thorough cooking renders all kinds of food more 

 digestible. Raw starch is indigestible. 



191. Green vegetables. There are many kinds of vege- 

 table food which supply little weight, heat, or energy to 

 the body, yet are often eaten because of their agreeable 

 taste. Beets, turnips, carrots, parsnips, pumpkins, and 

 melons are poor in albumin. They contain some starch 

 and sugar and much fibrous substance wholly indigestible. 

 Their agreeable taste may increase the flow of the diges- 

 tive fluids, and their bulk may excite the peristalsis of the 

 intestine. 



Tomatoes, cabbage, cauliflower, onions, asparagus, and 

 all other green vegetables are still poorer in food mate- 

 rial, and are especially liable to ferment in the intestine. 



Green vegetables, such as cucumbers, which are eaten 

 in an unripe state, are wholly indigestible. Thus they 

 may pass through the intestine almost unchanged, or they 

 may ferment and produce pain. 



192. Iron in vegetables. Green vegetables contain a 

 considerable quantity of iron-bearing albumin or nucleo- 

 albumin, while grain and animal food contain only a small 

 quantity. This form of albumin is easily destroyed in the 

 intestine if fermentation of food takes place. Under these 

 circumstances green vegetables, by furnishing an abun- 

 dance of this material, are a real food. Those should 

 be chosen which do not readily ferment. Of them all, 

 probably celery and spinach are best. 



193. Fruit. Fruits, such as apples, pears, plums, 

 peaches, and berries, have little albumin which man can 

 digest, but often have a large amount of sugar. Their 

 chief use is to fill the intestine when a food is eaten 

 which, like milk, leaves but little undigested matter to sweep 

 along with the bile and other waste matters. But all fruits 



