American Journal of Clinical Nutrition, Vol 20, 404-409, Copyright © 1967 by The American Society for Clinical Nutrition, Inc.

Fasting Plasma Amino Acids and Nitrogen Retention in Man following Prolonged Supplementation with Wheat Gluten or Egg Whites

¹ From the U. S. Army Medical Research and Nutrition Laboratory, Fitzsimons General Hospital, Denver, Colorado

Prolonged and excessive gluten or egg white administration in 17 volunteer subjects resulted in significant elevations of the fasting free glutamic acid and lesser rises in the proline concentration of the plasma. Changes in other amino acids were not significant. High gluten diets produced greater nitrogen utilization than diets supplemented with egg whites. In no case was the mean coefficient of digestibility for lipid, protein, or carbohydrate influenced by the prolonged dietary protein supplementation.

Our findings support the concept that plasma amino acid concentration, under the conditions of this study, may be dependent upon and qualitatively reflect the amino acid composition of the ingested protein after prolonged supplementation. These data, supplemented by prior studies from this laboratory, further suggest that elevation in fasting free plasma glutamic acid per se does not have a deleterious effect and therefore may not be of etiologic importance in the pathogenesis of nontropical sprue.