What are omega-3s?
Omega-3 fatty acids (EPA, DHA)
Omega-3s are a family of healthy fats, found mainly in oily fish, that your body builds into cell walls and uses to help switch inflammation off.
Think of omega-3s as the brakes in your body's inflammation system. Other fats help press the accelerator when you need a response; omega-3s help bring things back to a calm stop afterwards.
Why it matters for aging
The most important omega-3s, EPA and DHA, come from oily fish like salmon, sardines, mackerel and herring. Plants such as flaxseed and walnuts provide ALA, which the body converts to EPA and DHA only in small amounts.
DHA is a major building block of the brain and eyes. High-dose supplements can slightly raise the risk of atrial fibrillation, an irregular heartbeat, in some people, so more isn't always better.
A common myth
Fish oil supplements protect everyone's heart.
In the large VITAL trial of healthy adults, fish oil didn't significantly reduce major heart events. But in a 2025 analysis of older adults, it slightly slowed DNA-based aging clocks.
Go deeper
Deep dives
- Omega-3 and aging: what the newest data actually shows
- The best supplements for longevity, graded by evidence
Related terms
Updated Nov 9, 2026 · All terms