n-3 fatty acid dietary recommendations and food sources to achieve essentiality and cardiovascular benefits.
n-3 fatty acid dietary recommendations and food sources to achieve essentiality and cardiovascular benefits.
Year: 2006
Authors: Gebauer, SK, Psota, TL, Harris, WS, Kris-Etherton, PM.
Publication Name: Am. J. Clin. Nutr.
Publication Details: Volume 83, Page 1526S.
Abstract:
The purpose of this paper is to review both the current dietary recommendations for omega-3 fatty acids, and the existing data showing beneficial effects of omega 3 fatty acids, in order to summarize the intakes associated with a reduced risk of CVD. Positive associations between ALA intake and reduced risk of CVD have been noted in the National Heart, Lung, and Blood Institute Family Heart Study, the Nurses Health Study, and the Health Professionals Follow-up Study. Overall, these studies demonstrated that intakes of ALA ranging from 0.58 – 2.81 g/day are associated with a reduced risk of CVD all-cause mortality. Intervention studies, including the Lyon Diet Heart Study, have also been strongly supportive of the cardioprotective effect of ALA. However, it has been observed in some population studies that higher intakes of ALA may be linked to an increased risk of advanced prostate cancer. As such, the authors state that further research is warranted before firm recommendations can be made to increase ALA intakes beyond current levels. Similarly, the heart health effects of marine based n3 fatty acids (EPA and DHA) have also been demonstrated in numerous epidemiological and intervention trials. Recommendations to achieve nutritional adequacy, defined as the amount necessary to prevent deficiency symptoms, is 0.6-1.2% of energy for ALA, in which up to 10% of this can be provided by EPA or DHA. Evidence supports a dietary recommendation of » 500mg/day of EPA + DHA for cardiovascular disease risk reduction. For treatment of existing cardiovascular disease, 1 g/day of EPA+DHA is recommended. Dietary sources of ALA include flaxseeds and flaxseed oil, walnuts and walnut oil, canola oil and soybean oil. In addition to providing ALA, flaxseeds and walnuts are also a good source of other nutrients such as fiber, monounsaturated fatty acids, vitamins, and minerals. Cold water fish and fish oil are the primary food sources of EPA and DHA. Fish is also a good source of protein, B vitamins, and minerals such as potassium, phosphorous, and selenium. However, EPA and DHA are particularly vulnerable to oxidative breakdown leading to the development of food deterioration affecting flavor, aroma, color, texture, and nutritional value. Oxidation of EPA and DHA can occur in a relatively short period of storage time giving rise to unpleasant odors and unsavory flavor characteristics that, once generated, are difficult if not impossible to remove. Many people do not like fish and avoid it in their diets. In addition, concerns have been raised with regarding mercury and PCB contamination in some fish products. For the food industry, challenges exist in incorporation of omega 3 fatty acids into foods. Strategies are required to order to increase consumption of fish and plant-based omega 3 sources, fortified foods and fish oil supplements. Overall, a modest increase in intake can have important and beneficial public health outcomes.
