FOOD ACCESSORIES AND DRUGS 291 



influence upon gastric digestion. In healthy people this 

 is of little consequence, but when the digestive powers are 

 in any way impaired, the use of these beverages may be 

 inadvisable. The more important effect, however, of both 

 tea and coffee is in their stimulating action on the nervous 

 system. No satisfactory explanation has yet been given of 

 the fact that some people can use tea and not coffee, while 

 with others the reverse is true. It is probably safe to say 

 that when used in moderation, tea and coffee are usually 

 harmless to those leading an otherwise hygienic life. They 

 should be used sparingly by nervous people and by those in 

 whom digestion is feeble and slow (Hutchinson). Even by 

 the perfectly healthy they should not be used to excess, nor 

 should the habit be acquired of using them as the whip to 

 the tired horse. Drinking strong coffee in order to keep awake 

 for evening study is objectionable, and the substitution of 

 afternoon tea for a little rest or sleep is also unwise. 



5. Cocoa is made from the seeds of trees of the genus 

 Theobroma, and chocolate is prepared . from cocoa. In the 

 solid form both are highly nutritious, as shown by the 

 following average results of analyses: 



PROTEIN FAT CARBOHYDRATE 



Cocoa 21.6% 28.9% 37.7% 



Chocolate 12.9% 48.7% 30.3% 



When used as a beverage, however, the nutriment derived 

 from them is small. In addition, cocoa and chocolate both 

 contain theobromine, a substance closely related chemically to 

 caffeine and possessing much the same stimulating proper- 

 ties. In general, the same hygienic considerations which 

 apply to the use of tea and coffee should guide us also in 

 the use of chocolate and cocoa. 



6. Soda water and similar beverages. Of these little need 

 be said. In general, they are harmless enough, especially to 

 those enjoying perfect digestion. The large amount of sugar 



