CHEMISTRY AND FOOD 255 



CALORIES 



Carpentry 240 



Metal working 240 



Industrial painting 240 



"Active exercise" (bicycle ergometer) 290 



Walking actively (about 3f miles per hour) .... 300 



Stoneworking 400 



"Severe exercise" (bicycle ergometer) 450 



Sawing wood 480 



Running (about 5^ miles per hour) 500 



"Very severe exercise" (bicycle ergometer) .... 600 



This exact quantitative knowledge of the energy 

 values of foods and energy requirements in nutrition 

 now forms the basis of all sound practical work in food 

 chemistry and human nutrition whether it be a prob- 

 lem of an individual or a family, a nation or a whole 

 group of nations. During the World War the food 

 crops and the food needs of America and the Allies were 

 pooled and apportioned on the basis of calories; and 

 every individual who wishes to purchase food economic- 

 ally begins his or her planning by deciding first upon 

 the level of expenditure which is best expressed in terms 

 of the number of calories which must be bought with 

 a cent, or the number of cents which may be spent per 

 1000 calories of total food obtained. 



THE NUTRITIVE EFFICIENCIES OF FOOD PROTEINS. 

 Protein has long occupied a prominent place in studies 

 of food and nutrition and during the past decade much 

 new interest has been attracted to this factor in food 

 value by the discovery that the different proteins found 

 in foods may, when taken separately, show very differ- 

 ent efficiencies in nutrition. 



Dr. Thomas B. Osborne of the Connecticut Agricul- 



