382 AGRICULTURAL CHEMISTRY 



507. Dietary Studies. A dietary study considers the 

 cost and amount of nutrients consumed by individuals 

 and families. It is an investigation in which men are 

 used and human foods are studied instead of farm ani- 

 mals and animal foods. Dietary studies have shown that 

 frequently money is injudiciously spent in the purchase 

 of high-priced foods which contains but a small amount 

 of nutrients. In a dietary study, the amounts of nutri- 

 ents in the foods exclusive of the refuse parts are deter- 

 mined. From the weight of the foods, the nutrients 

 contained are calculated using the tables, or they are 

 determined by chemical analysis. 



The purchasing of food is frequently done without re- 

 gard to nutritive value. Erroneous ideas as to the 

 value of foods are often the cause of extravagance in 

 their purchase and use. As for example, it has been 

 claimed that the banana is as valuable as beef, and mush- 

 rooms have been erroneously called vegetable beefsteak. 

 Many other foods are assigned fictitious values. Too 

 frequently, choice is made on the basis of palatability, but 

 cost of nutrients and kind of work to be performed should 

 be considered as well as palatability. Dietary studies of 

 the United States Department of Agriculture have shown 

 that lack of knowledge in regard to the value of foods 

 has frequently resulted in whole families being underfed, 

 not from necessity but from lack of judgment in the se- 

 lection of foods. While it is not practicable or desirable 

 to confine the ration to an absolute standard, dietary 

 studies have shown that for long periods the best results 

 are obtained when foods are combined so as to secure nu- 



