American Journal of Clinical Nutrition, Vol 21, 836-843, Copyright © 1968 by The American Society for Clinical Nutrition, Inc.

Wheat Flour, Blood Urea Concentrations, and Urea Metabolism in Adult Human Subjects

¹ From the Department of Foods and Nutrition and Olin Health Center, Michigan State University, East Lansing, Michigan

When normal adult subjects were fed a diet providing 90-95% of their protein intake from wheat, their blood urea levels were half what they had been in the preceding control period. During the control period, the subjects consumed a mixed diet which was isonitrogenous with that for the experimental period (70 g protein/day). Practically all the protein in the wheat diets came from commercial white flour. The reduction in blood urea occurred in both men and women. In one study involving 12 normal men, the low blood urea levels continued for the 50 days the wheat diets were fed. The reduction in blood urea occurred largely within the first 48 hr after the wheat diet was started. It was accompanied by a slower but equally pronounced reduction in the blood non-protein nitrogen. No alteration in protein metabolism, as evidenced by urinary urea, creatinine, or uric acid excretion, accompanied the initial reduction in blood urea. This study indicates that the blood urea level may be influenced to a marked extent by the nature of the dietary protein.