Epidemiologic examinations of Greenland Inuit have disclosed a connection between high seafood intake containing a high level of n-3 polyunsaturated fatty acids (PUFAs) and a low coronary heart disease (CHD) morbidity. Other epidemiologic studies have confirmed this interrelation, and a biological substrate for a causal relationship has been established. This includes a lipid lowering effect of n-3 PUFAs and a modulatory effect on eicosanoid metabolism, shifting platelet vessel wall balance in an antithrombotic direction. Other metabolic effects of n-3 PUFAs are an altered inflammatory response to proinflammatory stimuli and a modest hypotensive effect. These findings create a basis for controlled clinical studies and justify, in the author's opinion, both a mass strategy of advocating that a well-balanced diet should include a higher use of seafood in Western diets, and a more intensive recommendation of n-3 PUFAs in certain high-risk patients with a heterogeneous risk-factor profile. Among these, patients with essential hypertension and patients undergoing reconstructive coronary intervention are obvious candidates. A major outcome of the research, stemming from the epidemiological studies, is establishment of the fact that separate attention should be paid to both the n-6 and the n-3 fatty acids.