Fish consumption and risk of major chronic disease in men.

BACKGROUND: Although fish consumption may reduce specific disease endpoints, such as sudden cardiac death and prostate cancer, the effects of major chronic disease on total burden, reflecting sums of effects on a variety of endpoints and risk pathways, are not well established. Higher n-6 fatty acid consumption has also been hypothesized to reduce the health benefits of n-3 fatty acids in fish.
OBJECTIVE: The aim was to study the associations of fish and n-3 fatty acid consumption with risk of total major chronic disease (cardiovascular disease, cancer, and death) and to determine whether a high n-6 intake modifies the associations.
DESIGN: Lifestyle and other risk factors were assessed every 2 y and diet every 4 y in 40,230 US male health professionals aged 40-75 y and free of major chronic disease at baseline in 1986. During 18 y of follow-up, 9715 major chronic disease events occurred, including 3639 cardiovascular disease events, 4690 cancers, and 1386 deaths from other causes.
RESULTS: After multivariable adjustment, neither fish nor dietary n-3 fatty acid consumption was significantly associated with risk of total major chronic disease. Compared with fish consumption of <1 serving/mo, consumption of 1 serving/wk and of 2-4 servings/wk was associated with a lower risk of total cardiovascular disease of approximately 15%. No significant associations were seen with cancer risk. Higher or lower n-6 fatty acid intake did not significantly modify the results (P for interaction > 0.10).
CONCLUSIONS: Modest fish consumption was associated with a lower risk of total cardiovascular disease, consistent with cardiac mortality benefits but not with total cancer or overall major chronic disease; n-6 fatty acid consumption did not influence these relations.