Omega-3 / Fish Oil

Omega-3 fatty acids (ALA, EPA, and DHA) are polyunsaturated fats found in fish, flaxseed, and dietary supplements such as fish oil, krill oil, and algal oil, most often used for heart-health and triglyceride support.

Supplement

What it is

Omega-3 fatty acids are found in foods such as fish and flaxseed and in dietary supplements such as fish oil, krill oil, cod liver oil, and algal oil. The three main omega-3s are alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA); ALA is essential and comes mainly from plant oils, while EPA and DHA come mainly from fish and seafood. The NIH Office of Dietary Supplements notes the FDA recommends no more than 3 g/day of combined EPA and DHA (up to 2 g/day from supplements), and that higher doses used to lower triglycerides should be taken under a healthcare provider's supervision because of potential bleeding and immune-function effects.

Food and timing considerations

Cold-water fatty fish (salmon, mackerel, tuna, herring, sardines), walnuts, chia seeds, and flaxseed, soybean, and canola oils are the main food sources, per NIH ODS.

Known interaction categories

Insufficient evidence
Informational
Monitor

Published interaction pages on this site

Related guides

Vitamin E, Omega-3, and Bleeding Risk

Sources

Omega-3 Fatty Acids - Health Professional Fact Sheet — NIH Office of Dietary Supplements Omega-3 Fatty Acids - Consumer — NIH Office of Dietary Supplements

Last reviewed 2026-08-24

Medical information disclaimer: this information is general and educational. It does not diagnose conditions, prescribe treatment, or determine whether a combination is safe for you personally. Follow your prescription label and ask a pharmacist or clinician before starting, stopping, or combining products. Full disclaimer.