Author Affiliations: Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute (Dr Oken); and Division of Newborn Medicine, Children's Hospital Boston (Dr Belfort), Boston, Massachusetts.
Fish are a rich source of long-chain n-3 (omega-3) polyunsaturated fatty acids (PUFA), essential nutrients that have important structural and physiological roles in several body systems, including neurological, immune, and cardiovascular. Because humans cannot synthesize n-3 PUFA, these nutrients must be consumed in the diet. Conversion from the parent n-3 PUFA, α-linolenic acid, to the more biologically active long-chain n-3 PUFA, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), is inefficient and therefore consumption of some preformed long-chain n-3 PUFA is important for optimal health. In the United States and elsewhere, fish is the main dietary source of DHA and EPA.
Oken E, Belfort MB. Fish, Fish Oil, and Pregnancy. JAMA. 2010;304(15):1717-1718. doi:10.1001/jama.2010.1541