178 



LIFE PROCESSES OF MAN 



Comparative Cost of Digestible Nutrients and Energy in Dif- 

 ferent Fooi> Materials at Average Prices 1 



It is estimated thai a man at light to moderate muscular work requires about 0.23 pound oi 



protein and 3,050 calories of energy per day. 



1 Principles of Nutrition and Nutritive Value of Food, W. C. Atwater, Farmers' Bulletin 

 No. 1 I-.'. 



*The cost of 1 pound of protein means the cost of enough of the given material to furnish 

 1 pound of protein, without regard to the amounts of the other nutrients present. Like- 

 wi-e the cost of energy means the cost of enough material to furnish 1,000 calories, without 

 reference to the kind> and proportions of nutrients in which the energy is supplied. These 

 estimates of t he cost of protein and energy are thus incorrect in that neither gives credit for 

 the value of the other. 



