Omega-3 fatty acidsWhat are omega-3 fatty acids?
Updated 9 Nov 2026
Short answer
Omega-3 fatty acids are a family of fats that the body uses to build cell membranes. Research focuses on three of them: ALA from plant oils, and EPA and DHA from fish.[1] The body cannot make ALA, and it turns less than 15% of ALA into EPA and DHA.[1]
ALA is in flaxseed, soybean and canola oils, chia seeds and walnuts. EPA and DHA are in fatty fish such as salmon, mackerel, herring and sardines.[1] Fish do not make them: microalgae do, and fish collect them through the food chain.[1] Supplements include fish oil, krill oil, cod liver oil, algae oil and flaxseed oil.[2]
Sources (2)
- Omega-3 Fatty Acids: Fact Sheet for Health Professionals. NIH Office of Dietary Supplements. ods.od.nih.gov
- Omega-3 Supplements: What You Need To Know. NIH National Center for Complementary and Integrative Health, 2024. www.nccih.nih.gov
More about omega-3 fatty acids
What is the difference between ALA, EPA and DHA?What are omega-3 fatty acids used for?Which foods are high in omega-3?Are omega-3 supplements safe?Does plant omega-3 (ALA) protect the heart?Does omega-3 lower blood pressure?For education; not medical advice. Talk to a doctor before you start, stop or change a supplement.