184 NUTRITION, DIETETICS AND ANIMAL HEAT 



food would keep a person indefinitely in good health. His de- 

 mands for nitrogen and carbon are always approximately the 

 same, but the organism revolts at being supplied with them from 

 exactly the same source for any considerable length of time. 

 As a diet is necessary (Schenck and Gurber): 



Proteid. Fat. Carbohydrates. 



Resting man 100 gm. 60 gm. 400 gm. 



Resting woman 90 gm. 40 gm. 350 gm. 



Working man 130 gm. 100 gm. 500 gm. 



It need scarcely be added that any condition, such as exer- 

 cise, temperature, etc., which increase the excreta, calls for a 

 larger supply of ingesta. Ordinary exercise is allowed for in 

 the estimates just given. 



ANIMAL HEAT. 



The Temperature. The average temperature of the human 

 body, taken under the tongue, is 98.5 F. It varies in different 

 parts, the mean being about 100. The metabolic activity in 

 different parts of the body is changeable, and consequently the 

 heat production in all parts is not the same. 



The fact that the temperature is nearly identical throughout 

 the body is due to the distribution of heat, which distribution is 

 mainly effected through the agency of the circulating fluids. 

 The rectal temperature is a little higher than that obtained in 

 the mouth. The temperature of arterial is higher than that of 

 venous blood. The warmest blood is in the hepatic veins; the 

 coolest is that which has just passed through the most exposed 

 peripheral parts, as the helix of the ear. The mean body tem- 

 perature is a little lower in the morning than in the evening, in 

 the female than in the male, on a restricted than on an abun- 

 dant diet, in cold than in hot climates, and, in general, in condi- 

 tions of diminished than of exalted metabolic activity. 



But in health these variations are of trivial importance and do 



