838 NUTRITION AND HEAT REGULATION. 



work is done, however, or in conditions of mental depression the 

 use of alcohol may remove the sense of fatigue and exhaustion 

 and lead to a sense of well-being. The most important work of 

 recent years has been directed toward determining the nutritive 

 value of alcohol. Does it function under any circumstances as a 

 food? Much depends in such a discussion upon the meaning of 

 the terms used. In the present brief statement it is to be under- 

 stood that by food is meant material which can be oxidized in 

 the body with the production of usable energy, but without in- 

 jurious effect upon the tissues, and moreover a material whose 

 consumption protects some of the other foodstuffs fats, carbo- 

 hydrates, and protein from destruction. In the first place, there 

 is no doubt that alcohol is oxidized in the body. Various observers 

 estimate that as much as 90 to 98 per cent, of the alcohol absorbed 

 is destroyed.* Since 1 gm. of alcohol, when burnt, yields 7 calories 

 of heat, it is evident that its oxidation in the body must yield a 

 large supply of heat energy. The question arises whether this 

 oxidation of the alcohol occurs in addition to the normal metab- 

 olism of the protein and non-protein foodstuffs, or whether it pro- 

 tects and takes the place of these foodstuffs. With regard to the 

 non-proteins a number of observers have attempted to determine 

 the point by ascertaining the total carbon excretion during an 

 alcohol period. If the usual amount of material is burnt, and the 

 alcohol in addition, it is evident that the carbon excretion should be 

 markedly increased. Most observers, however, find that it re- 

 mains practically the same. Such results as the following have 

 been obtained: 



, , ,. , f Alcohol-free days. . 251.9 ems. carbon. 



Atwater and Benedict ( Alcohol dayg > ^3^ * 



13.4 " 



-P / Alcohol-free days . . 212.58 gms. carbon. 

 ^ jerie \Alcoholdays 220.84 " 



-f 8.26 " 



n, f Alcohol-free days. . 214.83 gms. carbon. 

 C1 P att -\Alcoholdays 220.87 " 



+ 6.04 " 



These results indicate that the alcohol is used by the body in place 

 of the other carbon-containing foodstuffs. Geppert and Zuntz have 

 also found that on alcohol days there is no material increase in 

 the carbon dioxid eliminated or the oxygen absorbed. 



Theoretically if the alcohol takes the place of the other material the 

 amount of carbon dioxid excreted should be diminished. One gram of 

 alcohol when oxidized furnishes as much heat as 1.7 gms. of sugar or 0.75 gm. 

 of fat. But 1 gm. of alcohol when burnt yields only 1.91 gms. of CO 2 , while 

 1.7 gms. of sugar yield 2.77 gms. CO 2 , and 0.75 gm. of fat, 2.13 gms. of CO 2 . 



* See Atwater and Benedict, Bulletin 69, United States Department of 

 Agriculture, 1899. 



