New research by scientists suggests that fish oil may cause more damage than it can be repaired in people who have suffered repeated mild traumatic head injuries. The study found that eicosapentaenoic acid (EPA) may interfere with the brain’s ability to heal, disrupting blood vessel repair, weakening brain tissue stability, and contributing to neurodegenerative conditions like chronic traumatic encephalopathy. Mice given EPA-heavy diets showed slower recovery, poorer cognitive performance, and signs of long-term neurological damage. Researchers also found similar patterns in human brain cells and postmortem tissue from individuals with CTE. The implication is that the brain processes differently after an injury, creating a metabolic vulnerability.