UNITED STATES DEPARTMENT OF AGRICULTURE 
BULLETIN No. 751 
Contribution from the States Relations Service 
A. C. TRUE, Director 
Washington, D. C. 
PROFESSIONAL PAPER 
April 22, 1919 
EXPERIMENTS ON THE DIGESTIBILITY OF WHEAT 
BRAN IN A DIET WITHOUT WHEAT FLOUR. 1 
By Akthuk D. Holmes, Specialist in Charge of Digestion Experiments, Office of 
Home Economics. 
CONTENTS. 
Page. 
Review of previous investigations 1 
Methods of procedure 7 
Subjects 8 
Experimental diet 8 
Page 
Experiments with fine wheat bran 10 
Experiments with unground wheat bran 13 
General discussion 17 
REVIEW OF PREVIOUS INVESTIGATIONS. 
Wheat in some form constitutes a very large proportion of the 
average dietary. The larger part of the wheat used for human food 
is consumed in the form of bread, which ordinarily is prepared from 
one of three common types of wheat flour — white flour (commercially 
known in this country as standard patent), entire or whole- wheat 
flour, and graham flour. The importance of wheat in the American 
dietary is readily appreciated when it is noted that in normal times 
the annual per capita consumption is approximately 5 bushels ; 2 it 
has been estimated 3 that excluding wheat breakfast foods, macaroni, 
spaghetti, and similar foods, and referring only to the three common 
flours, patent, entire, and graham, they supply 20 per cent of the 
protein, and 26 per cent of the carbohydrate of the average dietary. 
In times of stress even greater reliance is placed on bread, and it is a 
matter of repeated observation that those of relatively small incomes 
tend to make bread a predominating portion of the diet. With the 
outbreak of the war, and the prospect of a diminished supply of 
some food materials, the question of a more complete milling of wheat 
1 Prepared under the direction of C. F. Langworthy, Chief, Office of Home Economics. 
2 U. S. Dept. Agr. Bur. Crop Estimates Rept., 3 (1917), No. 10, p. 99. 
3 U. S. Dept. Agr. Office Expt. Stas. Circ. 110 (1911), p. 26. 
85781°— Bull. 751—19 1 
