Another week, another study. Actually, it’s the commentary about the study that really grabbed my attention; the researchers used language like “fail” or “did not protect the brain” about a recent study on omega-3 fatty acid supplementation and cognitive ability. Let’s take a look at this study, and then we can decide for ourselves whether the science supports the commentary.

Researchers at the University of Southern California recruited over 300 subjects with specific physical and genetic profiles; they were attempting to find out whether two grams of high-DHA omega-3 fatty acid fish oil could improve or at least prevent the decline in cognitive ability. The researchers tested the change in omega-3 composition of cerebrospinal fluid as well as taking scans of the brain to see whether any shrinkage in specific areas of the brain occurred. They also did standardized cognitive testing to measure improvements or declines in cognition.

After two years, while there was improvement in the DHA ratio in the brain as evidenced by the increases in DHA in the cerebrospinal fluid, there were no differences in the cognitive testing nor specific brain regions. That led the researchers to conclude omega-3 fatty acids were of no benefit for improving markers for brain health in spite of the increase in DHA within the brain itself.

Are those comments warranted? And was that the real purpose of the study? We’ll take a deeper look in Saturday’s memo.

What are you prepared to do today?

        Dr. Chet

Reference: https://doi.org/10. 1016/j.ebiom.2026. 106316