IN RELATION TO THE WAR. 493 



attempt to reduce materially the amount of bread consumed will 

 often be much more difficult, and to limit the poor to a per capita 

 allowance of bread as small as that to which the wealthy can easily 

 limit themselves would involve both hardship and injustice. 



People of low income naturally and properly live more largely 

 upon bread, because it usually furnishes more food value in propor- 

 tion to its cost than any other prominent article of diet. For this 

 reason the saving- of wheat in the homes of the many can best be 

 effected by teaching them not to eat less bread but less wheat in 

 their bread. 



Because so many of our people must for economic reasons de- 

 pend so largely upon breadstufifs, it seems of the utmost import- 

 ance to determine as conclusively as possible the nutritive effi- 

 ciency of the chief wheat substitutes as compared with wheat itself. 

 A study of corn in this respect appeared particularly desirable, 

 because it is so much the most important quantitatively of the 

 grains which can be substituted for wheat and at the same time the 

 one whose equal value with wheat is perhaps the most apt to be 

 questioned, especially as regards its digestibility and the nutritive 

 efficiency of its proteins. 



In the experience of our laboratory,^ the abrupt substitution of a 

 large amount of corn meal for wheat flour, has sometimes, though 

 not necessarily, been followed by slight disturbance or discomfort 

 of digestion, but in all cases the corn protein has shown essentially 

 the same efficiency in nutrition as has the protein of wheat. Such 

 unfavorable effects upon appetite or digestion as were attributed to 

 corn meal may have been due to the methods of preparing the corn 

 products or to the fact that the diet as a whole was too bulky and 

 too starchy for the summer weather in which the earlier of our ex- 

 periments were performed. 



Not only the time and temperature of cooking but also the final 

 texture of the material may be a factor of some importance to its 

 digestibility. The porous texture of our ordinary wheat bread 

 favors the absorption of large quantities of saliva as the bread is 



1 The experiments with human beings here referred to were all made 

 upon healthy adults and relate to requirements for maintenance, not for 

 growth or reproduction. 



