Fish oil

Does fish oil help with depression?

Updated 4 Nov 2026

Short answer

The effect is small and uncertain. A 2021 Cochrane review of 34 placebo trials and 1,924 adults with major depression found a benefit of about 2.5 points on a standard scale. A change under 3 points is unlikely to matter in daily life, and the certainty was very low.[1]

A 2019 review suggests that products with at least 60% EPA, at up to 1 g of EPA a day, work better than those high in DHA.[2] Taking fish oil to prevent depression did not help. In 18,353 adults aged 50 or older, 1 g a day for 5.3 years gave 13.9 cases per 1,000 person-years against 12.3 on placebo, a small but significant rise. Mood scores did not change.[3]

Depression can be serious, so anyone who may have it should see a health care provider.[4]

Sources (4)

  1. Omega-3 fatty acids for depression in adults. Appleton KM, Voyias PD, Sallis HM, Dawson S, Ness AR, Churchill R, et al. Cochrane Database Syst Rev, 2021. PMID 34817851
  2. Efficacy of omega-3 PUFAs in depression: A meta-analysis. Liao Y, Xie B, Zhang H, He Q, Guo L, Subramanieapillai M, et al. Transl Psychiatry, 2019. PMID 31383846
  3. Effect of Long-term Supplementation With Marine Omega-3 Fatty Acids vs Placebo on Risk of Depression or Clinically Relevant Depressive Symptoms and on Change in Mood Scores: A Randomized Clinical Trial. Okereke OI, Vyas CM, Mischoulon D, Chang G, Cook NR, Weinberg A, et al. JAMA, 2021. PMID 34932079
  4. Omega-3 Supplements: What You Need To Know. NIH National Center for Complementary and Integrative Health, 2024. www.nccih.nih.gov

More about fish oil

What is fish oil?Does fish oil reduce inflammation?How much EPA and DHA is in a fish oil capsule?Is eating fish better than taking fish oil?What is fish oil used for?Should fish oil be taken with food?

For education; not medical advice. Talk to a doctor before you start, stop or change a supplement.