706 PLAIN FACTS FOR OLD AND YOUNG 



after eating ; while meats and vegetables require from 

 three to five hours for the completion of stomach diges- 

 tion in persons whose stomachs are in a normal condi- 

 tion; a still longer time is required when the digestion 

 is very slow. Milk is digested in one and one-half 

 hours. Boiled rice and other well-cooked grains are 

 digested in one to two hours. 



While it is well to introduce a considerable variety 

 of foodstuffs into the bill of fare, it is not wise to take 

 too many different kinds of food at a single meal. The 

 gastric juice which is best adapted to the digestion of 

 one food may be ill-adapted to the digestion of another. 

 Food containing a considerable amount of protein, for 

 example, requires a large amount of very active gas- 

 tric juice, while liquid foods containing a considerable 

 amount of fat, such as milk, cream, buttermilk, or rich 

 gravy, require very little gastric juice and diminish 

 the amount of gastric juice produced by the stomach. 

 It is evident, then, that the combination of two kinds 

 of foods might result disastrously, one food failing to 

 digest because of a deficiency of the necessary diges- 

 tive fluid, and the other remaining a long time in the 

 stomach after it should have passed on for treatment 

 in the small intestine. This is one of the causes of bil- 

 iousness, and it is for this reason that fats are gener- 

 ally known to be productive of ''biliousness" when 

 taken freely. The eminent physiologist, Pawlow, has 

 proven by experiments upon animals and human 

 beings that different foodstuffs require different sorts 

 of gastric juice for digestion, and especially made 

 clear the importance of simplicitj^ in dietetic habits. 



Persons who suffer from hyperacidity should avoid 

 the use of strongly acid fruits and starchy foods, and 



