New data from the EPIC-Norfolk Study in the U.K. revealed some surprises about blood levels of DHA in vegans. DHA is one of the long-chain fatty acids found primarily in fish oils. Vegans don’t consume any, but in this study, vegan women (although not men) had the highest levels of plasma DHA of all the groups.
Since DHA can be synthesized from another omega-3 fat, alpha-linolenic acid (ALA), one theory is that vegans are more efficient at converting ALA to DHA. And in fact, this study did find that those who don’t eat fish are better converters than those who do, and that women are better converters than men.
That might suggest that vegans—or at least vegan women—don’t need to worry about DHA. But the truth is that these particular results are probably an anomaly. Of the 4,902 subjects in the study, there were only 5 vegan women. And among those 5 subjects, there was a pretty wide range of DHA levels which means that some of the women had very low levels.
Since other research has shown that vegans have lower levels of DHA, it’s important to put these results into perspective. I certainly wouldn’t want to make recommendations regarding DHA supplements for vegans based on this tiny bit of data that isn’t quite in sync with other findings.
The whole story about DHA remains complicated and poorly understood. No one knows for certain whether or not vegans would benefit from having a source of DHA in their diet. And algae-derived supplements—the only DHA source for vegans—are expensive. But I take 200 milligrams of vegan DHA per day myself, and the EPIC-Norfolk study hasn’t changed my mind about doing so.