Contact sports can take a toll on the brain, even without obvious concussions, and new evidence indicates that repetitive, subconcussive head impacts may cause subtle but considerable brain injury over time. A recent review and analysis found that some evidence points to lower brain injury markers among athletes who took omega-3 fatty acid supplements—especially among those with higher play time—but overall, results are mixed.

Researchers conducted a systematic review and meta-analysis using data from three studies on American football players—who often receive multiple subconcussive head impacts during a typical season. They examined whether supplementation with omega-3s reduced levels of neurofilament-light, a protein that rises in the blood following brain injury.

They found that across the three studies, omega-3 supplementation reduced neurofilament-light levels by 60% to 100% compared to a placebo in one study, prevented marked increases in another, and showed no effect in the third, with reductions primarily observed in starter players.

A subconcussive head impact is a minor blow to the head that does not cause immediate symptoms of a concussion but can still lead to cumulative brain damage over time. Athletes frequently sustain hundreds of these minor impacts each season, allowing them to accumulate unnoticed. Because these injuries are usually asymptomatic, players may not receive the treatment or restrictions they need for recovery, exacerbating neurological damage.

These findings indicate that omega-3 supplementation may protect the brain from the cumulative effects of subconcussive head impacts in contact sports. However, the investigators cautioned that their review only included three studies—with mixed results—and further research is needed to establish the optimal dose and timing for this potential protective effect. Learn about the many health benefits of omega-3s in this episode featuring Dr. Bill Harris.