Americans spend approximately one billion dollars annually on omega-3 fatty acid supplements, primarily fish oil, hoping to protect against age-related cognitive decline. While omega-3s are known to enter the brain, a new study casts doubt on their effectiveness in preventing or significantly impacting conditions like Alzheimer’s disease. The research challenges the widely held belief that these supplements offer substantial brain health benefits. This finding is notable given the substantial financial investment in these products driven by concerns over aging populations. The study suggests the current understanding of omega-3’s impact on the brain may be overstated. Further research is needed to fully understand the role, if any, of omega-3s in neurodegenerative disease prevention. The findings raise questions about the value of widespread omega-3 supplementation for cognitive health.