N-3 Fatty Acids from Fish and Plants: Primary and Secondary Prevention of Cardiovascular Disease

Fish and fish oils contain the very-long-chained and highly polyunsaturated n–31 fatty acids which are derived from phytoplankton, the base of the food chain in the oceans, lakes, and rivers (1). Phytoplankton synthesize the n–3 fatty acids, eicosapentaenoic (20:5) (EPA) and docosahexaenoic acids (22:6) (DHA), which are subsequently incorporated into fish, shellfish, and sea mammals. The plants synthesize an n–3 fatty acid, linolenic acid (18:3), that can be converted by the body to EPA and more slowly to DHA (2,3). The n–3 fatty acids have profound biological and biochemical effects in the body. Despite a wealth of scientific information [a review listed over 120 references about cardiovascular effects alone (4)], clinical interest in n–3 fatty acids has not been high in the United States despite considerable attention to their use in Europe and Japan. This chapter will focus on the considerable and underappreciated potential benefits of the n–3 fatty acids in cardiovascular disease.