American Journal of Clinical Nutrition, Vol 22, 1459-1468, Copyright © 1969 by The American Society for Clinical Nutrition, Inc.

Lysine Enrichment of Wheat Flour: Evaluation in Infants

¹ From Grace Department of Research, British American Hospital, Lima, Peru, and Department of Pediatrics, Baltimore City Hospitals and the Johns Hopkins University, School of Medicine

The equivalent of 0.12% lysine enrichment of white wheat flour resulted in significant enhancement of its protein value for the rapidly growing human infant, as demonstrated by increased rates of weight gain and nitrogen retention, stability of serum albumin, and elevation of the molar ratio of plasma lysine when the flour was the only source of protein in the diet. Isonitrogenous and isocaloric casein diets were used as controls. Enrichment to the 0.2% level resulted in suggestive further increases in the rates of weight gain and N retention, a further elevation in the molar ratio of plasma lysine and a reduction in that of plasma threonine. Enrichment to the 0.4% level resulted in a suggestive further increase in N retention alone and in further elevation of plasma lysine and reduction of plasma threonine.

Enrichment of white wheat flour with lysine to the 0.12% and possibly the 0.2% level is recommended for those areas in which this cereal serves as the main source of protein in the diet, particularly that of infants and children. The improvement in biological value to be expected is enough to make the difference between dietary protein adequacy and deficiency to the many, without adverse effects to the few who might not profit by such enrichment.