Fish oil

Does fish oil reduce inflammation?

Updated 4 Nov 2026

Short answer

It lowers blood markers of inflammation in many trials, especially in people with health conditions. A 2026 review of 96 trials found lower CRP, TNF-alpha and IL-6, three such markers, and the most consistent results at 1 to 3 g a day.[1]

Results depend on the dose and the group. In two trials of people with high triglycerides, 4 g a day of purified EPA lowered CRP by 36% and 22%, while 2 g did not.[2] A review of high-dose EPA trials found no significant change in CRP.[3]

The effect on disease is less clear. In rheumatoid arthritis, CRP and disease scores did not fall significantly in a review of 18 trials.[4] In VITAL, 1 g a day gave 234 cases of autoimmune disease against 280 on placebo after 7 years. During the 5.3 years of treatment itself, the difference was not significant.[5]

Sources (5)

  1. Role of the EPA: DHA dosing ratio in omega-3 supplements on blood fatty acid profiles and inflammation: a systematic review and meta-analysis. Khabir Z, Abdelhafez A, Camponovo F, Joyce P, Garcia-Bennett A Crit Rev Food Sci Nutr, 2026. PMID 41568426
  2. Icosapent ethyl, a pure ethyl ester of eicosapentaenoic acid: effects on circulating markers of inflammation from the MARINE and ANCHOR studies. Bays HE, Ballantyne CM, Braeckman RA, Stirtan WG, Soni PN Am J Cardiovasc Drugs, 2013. PMID 23325450
  3. Formulation-Specific Cardiovascular Outcomes with High-Dose Eicosapentaenoic Acid: A Systematic Review and Meta-analysis. Faheem MA, Azeem B, Ali T, Asim R, Muhammad TS, Dogar ME, et al. Am J Cardiovasc Drugs, 2026. PMID 42070013
  4. Effects of omega-3 supplementation on lipid metabolism, inflammation, and disease activity in rheumatoid arthritis: a meta-analysis of randomized controlled trials. Wang W, Xu Y, Zhou J, Zang Y Clin Rheumatol, 2024. PMID 38922552
  5. Vitamin D and Marine n-3 Fatty Acids for Autoimmune Disease Prevention: Outcomes Two Years After Completion of a Double-Blind, Placebo-Controlled Trial. Costenbader KH, Cook NR, Lee IM, Hahn J, Walter J, Bubes V, et al. Arthritis Rheumatol, 2024. PMID 38272846

More about fish oil

What is fish oil?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?Does fish oil prevent heart attacks?

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