62 



MAN, — THE ANIMAL 



cells have a special selective capacity in taking food 

 from the blood, it is impossible to conceive how 

 one set of cells, like the brain, for example, can be 

 furnished with a specific food. There is no evi- 

 dence that this is the case. There is also no evi- 

 dence in support of the popular contention that the 

 brain cells need a special kind of food even if there 

 were some special mechanism that would assist 

 them in taking it From the blood stream. 



When a group of foods is chemically analyzed, 

 it is found that they are very similar as the follow- 

 ing table shows : 



Table 2. — Ash Constituents of Some Common Fruits.* 



•Sherman, H. C: Chemistry of Food and Nutrition, p. 332. 



The chemical elements found in these foods are 

 the ones that are most abundant in living proto- 

 plasm and in nature. (Fig. 17.) 



