Establishing Dietary Reference Intakes for EPA + DHA (Workshop Report)
Reference:
Harris, WS et al., J. Nutrition, 139: 804S-819S , 2009
Report from the workshop entitled “Towards Dietary Reference Intakes for Omega-3 Fatty Acids “ held in Washington, DC (June 4-5, 2008) as sponsored by the Technical Committee on Dietary Lipids of the International Life Sciences Institute (North America)
Summary:
The present publication reports upon the 2008 workshop wherein the body of evidence from the peer-reviewed literature was evaluated by a wide array on scientific experts with expertise in the omega-3 /health area to determine if the cumulative evidence is sufficient to justify the establishing of Dietary Reference Intakes (DRI) for EPA plus DHA. It is noted that , in 2002, the Institute of Medicine concluded that insufficient evidence was then available to define a DRI for EPA/DHA over and above that established for LNA (alpha-linolenic acid) . The latter body did indicate that EPA plus DHA could contribute (although not obligatory) up to 10 % towards the DRI as set for LNA.
The present report on the 2008 workshop concluded that ‘ consistent evidence from multiple research paradigms demonstrates a clear, inverse relation between EPA + DHA intake and risk of fatal (and possibly nonfatal) CHD, providing evidence that supports a nutritionally achievable DRI for EPA+DHA between 250 and 500 mg/day’. The report also indicated that evidence for EPA/DHA having beneficial effects on cognitive decline are emerging but not yet sufficient to recommend an intake of EPA/DHA which is different from the 250-500 mg/day for CHD (coronary heart disease) risk reduction. EPA+DHA were considered not to reduce the risk for cancer . The recommended intakes of EPA+DHA were not considered harmful.
This report on the 2008 workshop relied heavily on the published inverse relationships between EPA/DHA intakes from fish/fish oils and fatal cardiac events in justifying target intakes of 250-500 mg/day for the general population. Such a recommended intake is approximately 2-3 times current average intakes in North America . It is noted that the dietitians of North America recommended a target intake of 500 mg/day in their 2007 guidelines (J. Am. Dietetic Assoc., 107: 1599 (2007). A major review (meta-analysis) of studies on fish consumption and coronary heart disease mortality (He et al., Circulation, 109: 2705 (2004)) indicated that five or more fish servings per week were considerably more protective than two fish servings per week. Five servings/week would provide an estimated intake (EPA plus DHA) averaging at least 650 mg/day with seven servings/week providing approximately 900 mg/day. It appears that 650-900 mg/day as per 5-7 fish servings /week (or via functional foods/nutraceuticals) may well offer better protection for the general public than 250-500 mg/day.
Finally, DHA omega-3 is well recognized as a physiologically-essential nutrient in the brain and retina for optimal neuronal functioning and visual performance , respectively, and that some sectors of the population (eg., some infants) with very little capacity for converting LNA to DHA may well benefit by consuming DHA as a pre-formed nutrient. Also, various international groups have concluded that pregnant and lactating women need to consume at least 200 mg of DHA/day (Br. J. Nutr., 98: 873 (2007)). A focus on DHA omega-3 as an essential nutrient with specific DRI values for such vulnerable groups is worthy of major attention independent of the focus on EPA/DHA for reducing cardiac mortality (without diminishing the importance of this topic as covered in the present report).