CHEMICAL CONSTITUENTS OF BODY AND FOOD. 45 



cylic acid and benzoic acid to preserve it. In excess it gives rise 

 to rheumatism, gout, and bilious attacks, due to diminished excretion 

 of waste-materials from the economy. Wines contain from 6 to 25 

 per cent, of alcohol. Port holds 10 per cent, and sherry 16 to 25 per 

 cent, of alcohol. Besides, the aroma is due to ethers. Champagnes 

 contain in addition, 10 per cent, of sugar, which upsets the stomach. 

 Wines also have free acids, especially tartaric, which also disagree 

 with certain stomachs. 



Spirits contain about 50 per cent, of alcohol. Alcohol is a 

 nutrient and heat-generator. One gram of alcohol produces more 

 heat than one gram of proteid or carbohydrate. Ordinarily the sys- 

 tem can oxidize daily about one and one-half ounces of alcohol. When 

 alcohol is oxidized it spares the fats and carbohydrates and probably 

 the proteids. It is well known that the continuous drinking of 

 alcohol makes a person fat. The persistent use of alcohol also 

 increases the dangers of infection from infectious diseases. In fevers 

 its use prevents the loss of fat and stimulates the secretion of gastric 

 juice. It dilates the capillaries of the skin either by a local or central 

 action, favoring heat-dissipation. Its habitual use gives rise to 

 chronic gastritis and cirrhosis of the liver. The odor of spirits in 

 the breath is due to fusel-oil. Alcohol in the blood is changed into 

 carbonic acid and water. 



Coffee. Each cup of coffee contains about two grains of caffeine. 

 Coffee also contains a volatile substance called coffeon, which resem- 

 bles an oil. The exhilaration after the drinking of coffee and the 

 increased peristalsis are due to the coffeon. 



Tea. Tea contains caffeine and theophylline and about 7 per 

 cent, of tannin. Tea induces constipation and chronic gastritis when 

 used in excess. Neither tea nor coffee diminishes metabolic changes. 



Cocoa. This body is a nutrient because it contains fat (50 

 per cent.) and an albuminous substance. It contains theobromine. 

 Caffeine and theobromine belong to the purin group. 



