494 SYMPOSIUM ON FOOD PROBLEMS 



chewed, while soft or very crumbly corn bread (or corn meal mush) 

 may be swallowed without such thorough insalivation, and be less 

 readily digested for this reason. By baking corn bread in thin 

 scones it is possible to secure thorough and uniform cooking of the 

 starch and a final product hard enough to induce thorough mastica- 

 tion and admixture with saliva before swallowing. Thus prepared 

 and eaten, corn meal has in our later experiments replaced wheat 

 flour entirely with no detriment whatever to the ease and comfort of 

 digestion, even though the corn bread was the chief part of the diet. 



Recently we have completed an experiment in which a young 

 woman of average weight (56 kilograms), not previously accus- 

 tomed to any considerable use of corn foods, has substituted such 

 corn bread for all other bread stufifs and cereals for a month with 

 no disturbance whatever of appetite or digestion, and has main- 

 tained nitrogen equilibrium throughout the month on a diet furnish- 

 ing only 36 grams of protein daily, of which three fourths was the 

 protein of corn meal. Practically one fourth of the total protein 

 was furnished by milk and an insignificant amount by apple. Small 

 amounts of sugar and of filtered butter fat were used to bring the 

 fuel value of the diet up to the energy requirement. The subject 

 felt excellently nourished and was ready at the first opportunity to 

 begin a similar experiment even with the diet still further restricted 

 by omission of the milk. During 16 days on a ration of corn meal, 

 apple, butter-fat, and sugar, furnishing only 4.38 grams of nitrogen 

 or 27 grams of protein (equivalent to 34 grams for a man of 70 

 kilograms) practically all of which was maize protein, the loss of 

 body nitrogen was only about one half gram per day. 



It is evident from these experiments that the conclusion of Karl 

 Thomas, often quoted on Rubner's authority, which attributed a 

 much lower value to maize protein, was erroneous. In meeting the 

 maintenance requirements of adult human nutrition, the protein of 

 corn meal has here shown as high an efficiency as has been reported 

 by other investigators for wheat protein or for the average protein 

 of ordinary mixed diet. The well-established differences of nutri- 

 tive efficiency among proteins, corresponding to their differences in 

 chemical structure, are fully recognized but are more significant for 

 growth than for maintenance. Moreover we are here discussing 



