80 



POOD ACCESSOEIES 



fat and stored in the body for future use. Alcohol is never 

 stored for any length of time in the body, but is oxidized 

 at once. On this account fats and carbohydrates can 

 serve as sources of reserve energy, alcohol, never. 



Compared with the other fuel foods, the amount of 

 energy that a given amount of alcohol can produce when 

 completely oxidized is shown in the following table : 



In other words, the complete oxidation of a given amount 

 of alcohol produces 1.73 times as much energy as the same 

 amount of proteid or carbohydrate and 0.73 as much as 

 the same amount of fat. 



In ordinary digestion not all of the fat, carbohydrate, 

 and other nutrients which are taken in as food are actually 

 used by the tissue. The proportion of any substance 

 which actually reaches the tissues and is used by them is 

 called the availability of that nutrient. The availability 

 of the above four nutrients as actual energy producers for 

 the tissues is as follows: alcohol, 98%; proteid, 70%; fat, 

 95%; carbohydrate, 92%o- In other words, 98% of all 

 the alcohol taken, up to the safe limit, is at once trans- 

 formed into energy as against 70%, 92%, and 95% of a 

 similar amount of proteid, carbohydrate, or fat. 



One of the uses of ordinary nutrients is to preserve 

 other nutrients from oxidation. For example, the carbo- 

 hydrate which we eat keeps our body from using up the 

 proteid and fat of the body for its energy supply, or the 



