352 FOOD AND NUTRITION 



needed to furnish protein enough for a man of sedentary occupation. 

 How many eggs will be required per day if eggs are to furnish the 

 protein for the body? Weigh a quart of whole milk and by use of 

 Table XIV or Fig. 248 calculate the weight of milk a man would 

 have to consume daily to furnish 3.5 oz. of protein. Calculate the 

 weight of round steak needed to furnish 3.5 oz. of protein. 



FIG. 247. Composition of the FIG. 248. Composition of whole 

 whole egg. milk. 



391. How Much Food? The food eaten must, not only sup- 

 ply protein to keep the body in repair, but it must also furnish 

 enough energy for the needs of the body. The ability of foods 

 to produce energy in the body is measured by the amount of 

 heat they produce when burned. This is determined by burn- 

 ing the food in a calorimeter just as the heat value of coal 

 or other fuels is determined (Art. 122). Now the food require- 

 ments of the body are measured in heat units, usually the 

 greater calorie (Art. 121). Dr. Atwater in Farmer's Bulletin 

 No. 142, U. S. Department of Agriculture, gave the follow- 

 ing as the energy requirements per day for persons in different 

 occupations : 



Man with hard muscular work 4150 greater calories 



Man with moderately active muscular work . . . 3400 greater calories 

 Man at sedentary or woman with moderately 



active work 2700 greater calories 



Man without muscular exercise or woman at 



light to moderate work 2450 greater calories 



