Q: Is there a daily recommended intake for EPA and DHA, the two main omega-3 fats found in fish?
A: The U.S. has no official RDA or Daily Value for these long-chain polyunsaturated fats that have been linked to reduced risk of cardiovascular disease and other possible benefits. Found primarily in fatty fish, EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) are not “essential” nutrients because the body can make them, in limited amounts, from an omega-3 fat found in plant foods, called alpha linolenic acid, for which a daily Adequate Intake has been set: 1,100 milligrams a day for women, 1,600 milligrams for men.
But other health authorities across the world have issued EPA/DHA recommendations—which vary widely, reflecting the uncertainty about how much is needed for optimal health and disease prevention. For instance, several countries in Europe recommend 250 milligrams of EPA/DHA a day, on average, for healthy adults. Australia and New Zealand recommend less (160 milligrams), France more (500 milligrams). Russia tops the list, at 1,300 milligrams daily.
In April 2016, the Global Organization for EPA and DHA Omega-3s (GOED), a U.S.-based trade association, endorsed a daily recommendation of 500 milligrams—in line with the recommendation of the Chicago-based Academy of Nutrition and Dietetics.
To put these numbers into perspective, a 4-ounce serving of salmon has about 1,200 to 2,400 milligrams of EPA/DHA; rainbow trout, about 1,200 to 1,400; canned sardines, about 1,200 to 1,600; and canned tuna, about 300 to 1,000. If you eat at least two servings of fish a week—what the American Heart Association (AHA) recommends for general heart health—it’s fairly easy to get an average of about 250 milligrams a day(more or less, depending on your selections and portion sizes).
Our advice: The science on omega-3s is in flux. Still, if you like seafood, it’s reasonable to aim for two or more servings a week of fatty fish, which would supply the middle-of-the road amounts of EPA/DHA that most authorities advise. (Americans now average about 100 milligrams a day.) Choose a variety of fish to limit exposure to contaminants that any one particular type might have.
What about fish oil capsules instead of fish? Well-designed clinical trials on the supplements have produced mostly disappointing findings, perhaps because the benefits may really come from other components of fish rather than the omega-3s—which is why we recommend fish first.
Also see Balancing Omega-3 and Omega-6 Fats.