Fish Oil's Brain-Boosting Rep Takes a Hit

Fish oil's reputation as a brain booster just took a hit, at least in one very specific circumstance. A new study in Cell Reports found that eicosapentaenoic acid (EPA), a key omega-3 found in many fish oil supplements, appeared to slow brain recovery in mice that had repeated traumatic brain injuries that were still mild enough for the mice to recover without long-term damage. Those EPA-fed mice showed poorer blood vessel repair in the brain, more signs of cognitive trouble, and increased buildup of tau, a protein associated with conditions like chronic traumatic encephalopathy (CTE), per a release.

Docosahexaenoic acid, or DHA, the other big omega-3 in fish oil, didn't show the same potential downside: Its levels remained stable, and it wasn't linked to impaired healing. Researchers also saw hints of EPA-related repair problems in brain cells from people who had CTE. Still, the work is early and based on animals. Lead author Onder Albayram stresses to Gizmodo that he isn't labeling fish oil as universally good or bad, but he says the findings highlight that "biology is context-dependent," and that more research is needed on how EPA behaves in the brain, especially after injury.