CHAPTER XIII 



WHAT TO EAT • 



Questions. 1. Why can we not safely trust our instincts in deciding 

 what to eat or what not to eat ? 2. Why can we not always safely trust 

 our feelings in deciding how much to eat ? 3. Why can we not always 

 depend upon the customs of people in deciding how much to eat or what 

 kinds of food are good ? 



117. Why eating must be learned. We should expect that 

 in half a million years or more the human race might have 

 learned all there was to know about what to eat and how to eat 

 it. Most people, however, do not know, either from instinct or 

 from daily experience, the best way to manage their personal 

 food problems. Everywhere children suffer from defective nu- 

 trition and grown folks from disturbances of digestion. Starva- 

 tion and overfeeding exist side by side. 



Although all living beings consist fundamentally of proteins, 

 fats, and carbohydrates, not all plant or animal stuff is suitable 

 for food. Some plant and animal materials are not pleasant to 

 the taste, or are even disagreeable, and others are poisonous; 

 and some contain too little usable or digestible substance to be 

 worth eating. In the course of ages human customs have se- 

 lected the plant and animal materials in any given region that 

 are most valuable as food. W^e know that some parts of animals 

 and plants (muscle, grain) are better than others (hide, wood) ; 

 but experience has not taught us what proportions of meat and 

 grain and fruit are the best for bodily comfort and efficiency, 

 and we still have to learn that one combination is best for one 

 person, and another combination for others. With the increase 

 in travel, communication, and transport we are constantly dis- 

 covering useful food plants and food animals, and neither our 

 instincts nor our customs tell us the best way to use them. 



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