Effects of gamma-tocopherol supplementation on thrombotic risk factors.
The antioxidant activity of vitamin E is derived primarily from alpha-tocopherol (alpha-T) and gamma-tocopherol (gamma-T). Results of epidemiological studies have demonstrated an inverse relationship between vitamin E intake and coronary disease. However, the results of clinical trials using alpha-T are equivocal. We determined the effect of 5 weeks of 100 mg/d or 200 mg/d gamma-T supplementation on thrombotic markers such as platelet reactivity, lipid profile and the inflammation marker C-reactive protein (CRP).
METHODS AND RESULTS:
Fourteen healthy subjects consumed 100 mg/day while 13 consumed 200 mg/d of gamma-T and 12 received placebo (soybean capsules with less than 5 mg/d gamma-T) in a double-blinded parallel study design. Fasting pre and post dose blood samples were analysed. Blood gamma-T concentrations increased significantly (p<0.05) relative to dose during the intervention period. Both groups receiving active ingredients showed significantly lower platelet activation after supplementation (p<0.05). Subjects consuming 100 mg/d gamma-T had significantly decreased LDL cholesterol, platelet aggregation and mean platelet volume (MPV) (p<0.05). Little effect of gamma-T was observed on other parameters.
These data suggest that gamma-T supplementation may have a permissive role in decreasing the risk of thrombotic events by improving lipid profile and reducing platelet activity.