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Which is better: flaxseed oil or fish oil?
There are three omega-3 fatty acids, and, unfortunately, they are not equal in value. Flaxseed oil provides ALA (alpha-linolenic acid) while cold-water fish and fish oil provide EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid).
The majority of research on the health benefits of omega-3s – which include improving mood, supporting healthy circulation, reducing cardiac arrhythmias, lowering triglycerides and significantly reducing inflammation – has been done on EPA and DHA. The direct health benefits of ALA are far less clear.
The body can technically convert ALA into the more potent omega-3s (EPA and DHA) but it does a lousy job of it, converting as little as a half-percent to, in some studies, as much as five to nine percent. (Women seem to convert a bit more effectively than men.)
What makes matters worse is that omega-6 fatty acids, such as those found in safflower oil, sunflower oil, corn oil the like, interfere with the conversion of ALA to EPA and DHA. Vegetarians and vegans who get all their omega-3s from plant foods are also likely to be consuming a lot of omega-6s from vegetable oils, putting them at a double disadvantage.
To learn more, we recommend reading Form of Flax.
The science is pretty clear that if you want the demonstrated benefits of omega-3s, you’re better off with fish oil (EPA and DHA). But if you’re a vegetarian or vegan and can only consume plant-based omega-3s such as flaxseed oil (ALA), forget the capsules and take the oil, preferably 1.5 to 3 grams a day. (That way, even at a low rate of conversion, you’ll be getting a decent dose of the valuable EPA and DHA.) And reduce your consumption of high omega-6 vegetable oils. The ideal ratio for omega-6 to omega-3 is between 1:1 and 4:1; most people consume around 15:1,and that’s a bad situation whether you’re vegetarian or not!
None of this is to say that flaxseeds and flaxseed oil aren’t good for you! Flaxseeds contain prospective anticancer chemicals called lignans, and some flaxseed oils are designed to be “high-lignan.” Ground flaxseeds are a good source of fiber. Sprinkle them on everything!