EFFECT OF EXTREME FISH CONSUMPTION ON DIETARY AND PLASMA ANTIOXIDANT LEVELS AND FATTY-ACID COMPOSITION

Objective: To assess the effects of high-fish and low-fish diets on pl asma concentrations of fatty acids and selected antioxidants. Design a nd subjects: The effects of fish consumption on dietary and plasma ant ioxidant levels and fatty acid composition were studied as part of a l arge dietary survey of Finnish adults (n = 1861). High-fish consumers were matched with low-fish consumers and 41 pairs were identified. The members of each pair were of the same sex, from the same 10 y age gro up, and from the same or adjacent areas. There were 21 men and 20 wome n in each group, with a mean age of 54.3 y. Methods: The fish consumpt ion of the subjects was investigated with a qualitative food questionn aire. Additionally, a 3 d food record was used to estimate the diet, T wo indices were defined to describe the oxidation potential of the die ts. The plasma alpha-tocopherol, gamma-tocopherol, and beta-carotene c oncentrations and various fatty acids were analysed. Results: The mean fish intake was 103 g/d in the high-fish and 5 g/d in the low-fish gr oup. The dietary intakes of vitamin C, protein, total n - 3 polyunsatu rated fatty acids (PUFA), eicosapentaenoic acid, docosahexaenoic acid, mercury, selenium, and salt and the theoretical oxidative potential w ere higher (P < 0.05) and the saturated fatty acid intake lower (P < 0 .01) in the high-fish than in the low-fish group. The dietary vitamin E intake was similar in both groups but the ratio of dietary vitamin E /PUFA was higher (P < 0.01) in the high-fish than in the low-fish grou p (0.85 and 0.75, respectively). The plasma n - 3 PUFAs were higher (P < 0.001) and n - 6 PUFAs lower (P < 0.001) in the high-fish than in t he low-fish group. There were no differences in plasma antioxidant lev els between the groups. Conclusion: This study shows that extreme fish consumption does not affect plasma antioxidant levels.