Most American diets provide at least 10 times more omega-6 than omega-3 fatty acids. There is now general scientific agreement that individuals should consume more omega-3 and fewer omega-6 fatty acids for good health. It is not known, however, whether a desirable ratio of omega-6 to omega-3 fatty acids exists for the diet or to what extent high intakes of omega-6 fatty acids interfere with any benefits of omega-3 fatty acid consumption. Tufts EPC investigators reviewed the Third National Health and Nutrition Examination Survey (NHANES III; 1988-1994) database to examine intakes of omega-3 fatty acids in the United States. They found that men consumed significantly less ALA than women, adults consumed more than children, and those with a history of CVD consumed less than those without CVD (when energy intake was taken into account in the analysis). On any given day, only 25% of the population reported consuming any EPA or DHA. Average daily intakes were 14 g LA, 1.33 g ALA, 0.04 g EPA, and 0.07 g DHA.
ALA is present in leafy green vegetables, nuts, vegetable oils such as canola and soy, and especially in flaxseed and flaxseed oil. Good sources of EPA and DHA are fish (both finfish and shellfish and their oils and eggs) and organ meats. LA is found in many foods consumed by Americans, including meat, vegetable oils (e.g., safflower, sunflower, corn, soy), and processed foods made with these oils. The Institute of Medicine has established Adequate Intakes for ALA and LA (1.1-1.6 g/day and 11-17 g/day, respectively, for adults) but not for EPA and DHA.
