Effect of fish-oil and vitamin E supplementation on lipid peroxidation and whole-blood aggregation in man.

Free-living, healthy young men aged 21-35 years were divided into two groups, each group received dietary supplements of 15 g/day of fish-oil in the form of MaxEPA capsules, with or without an extra 400 I.U. of vitamin E, for two periods of four weeks. Blood samples were taken from an antecubital vein at two-week intervals. Plasma thiobarbituric acid reactive substances, conjugated dienes, vitamin E, creatine kinase, glucose and serum cholesterol were determined. Whole blood aggregation in response to collagen was determined by an electrical impedance method. Fish oil supplementation increased plasma thiobarbituric acid reactive substances after two weeks in vitamin E supplemented and non-supplemented groups but values returned to normal after four weeks in both groups regardless of the type of supplement given. No comparable increase in plasma conjugated dienes, creatine kinase or serum cholesterol was observed, the latter did not change significantly with diet. Plasma glucose increased when fish oil was supplemented, but only in the absence and not in the presence, of vitamin E supplementation. Whole blood aggregation decreased with the dietary fish oil in the presence, but increased in the absence, of vitamin E supplementation. These findings indicate an increased requirement for dietary antioxidant with high intakes of fish oil concentrates in man.