Vitamin E concentrations in human blood plasma and platelets

Vitamin E (tocopherol), cholesterol, triglyceride, and total lipid concentrations were determined in the plasma of 49 healthy, human, male subjects ranging in age from 24 to 91 yr. Tocopherol concentrations in the blood platelets of these subjects were also determined. α and γ tocopherol accounted for nearly all of the vitamin E compounds in plasma and platelet samples. The mean γ tocopherol concentration was one-fourth of that of α in both plasma and platelets. The α and γ tocopherol concentrations in plasma showed statistically significant positive correlations with total lipid, cholesterol, and triglyceride concentrations. However, the platelet α and γ tocopherol concentrations were not significantly correlated with plasma lipid, cholesterol, or triglyceride concentrations. Thus platelet vitamin E concentrations do not passively reflect plasma lipid changes and are postulated to be better indicators of vitamin E nutritional status than plasma tocopherol concentrations.