Fish Oil Boosts Building Blocks for Inflammation-Resolving Compounds

This meta-analysis combined data from 11 clinical trials (810 participants) to see whether omega-3 fatty acid supplementation (EPA and DHA) raises levels of two specific compounds in the blood — 18-HEPE and 17-HDHA. These compounds are precursors to specialized pro-resolving mediators (SPMs), molecules thought to help the body actively resolve inflammation rather than just suppress it.

The researchers found that omega-3 supplementation significantly increased both precursor compounds across the studies reviewed. Interestingly, the increase was more pronounced in people with existing inflammatory, metabolic, or oxidative stress — such as those with peripheral artery disease, chronic kidney disease, major depression with obesity, or pregnant women — while the effect was minimal in healthy infants.

The authors note this research was partly motivated by interest in how omega-3s might support mood, since EPA and DHA levels in the brain itself are very low, suggesting other pathways like SPM production could be involved. However, this study only measured the precursor molecules, not the final SPMs themselves or any mood-related outcomes, so more targeted research is needed to confirm a direct link.