Ingestion of Wheat Germ in Healthy Subjects Does Not Acutely Elevate Plasma Wheat Germ Agglutinin Concentrations

Abstract

Dietary fiber content (15 g/day) of the typical U.S. diet is considerably lower than recommended values (25–30 g), hence the public is encouraged to increase consumption of whole grains, fruits, and vegetables. Whole grains are a rich source of the lectin wheat germ agglutinin (WGA), which has been poorly studied in humans but has elicited adverse health effects in laboratory animals. It is unclear if it can breach the gut barrier, enter circulation, and influence physiology. Apart from animal studies, characterization of lectin behavior in humans is limited to tomato lectin (TL) and peanut lectin (PNA) feeding studies; both of which were able to detect lectin in systemic circulation within hours of ingestion of tomato juice and peanuts, respectively.The purpose of this study was to determine if WGA enters the circulation of healthy subjects following ingestion of wheat germ. Fourteen normal males and females between 17 and 40 yrs completed preliminary screening and reported to the lab after an overnight fast. Following baseline blood measurements, subjects consumed 50 g wheat germ within a 60 min interval. Blood samples were obtained at 30, 60, 90, 120, 240 min, and at 24 hrs post ingestion. Venous plasma concentrations of WGA were determined via WGA‐specific Enzyme‐Linked Immunosorbent Assay (ELISA) at the six time intervals, including baseline.According to the protocol utilized, WGA was not detected in venous plasma samples from any of the subjects following consumption of 50 g of wheat germ. Further research will be required to determine if WGA enters the bloodstream and binds formed elements such as erythrocytes, platelets, and leukocytes in addition to other tissues and organs. This research was supported by the department of Health and Exercise Science, Colorado State University.