Written from the studies on PubMed, searched on 2026. nov. 11.. Every number below comes from a study listed under Sources.
The claim
Posts online say that omega-3 fatty acids (fish oil) helps with ulcerative colitis.
Where research stands
We found 41 published papers on omega-3 fatty acids (fish oil) and ulcerative colitis. They were published between 1989 and 2026. 9 of them are studies in people. 9 of them compared people who got it with a group that did not. 10 were studies in animals, and none was only in cells in the lab. 5 papers are reviews that sum up other studies.
- 9In people9 with a comparison group
- 10In animals
- 0Only in the lab
What the studies found
We have not summed up these studies in words yet. The most important papers are listed under Sources.
Verdict
Omega-3 fatty acids (fish oil) has been tested in randomised trials in people with ulcerative colitis.
What this means for you: A study in people is not proof that it helps you. Do not stop or change your medicines because of it. Ask your doctor before you start taking it.
Sources
- Eicosapentaenoic Acid Reduces Fecal Levels of Calprotectin and Prevents Relapse in Patients With Ulcerative Colitis.2018 · Clin Gastroenterol Hepatol · Randomised trial
- An oral supplement enriched with fish oil, soluble fiber, and antioxidants for corticosteroid sparing in ulcerative colitis: a randomized, controlled trial.2005 · Clin Gastroenterol Hepatol · Randomised trial
- Decreased oxidative stress in patients with ulcerative colitis supplemented with fish oil omega-3 fatty acids.2003 · Nutrition · Randomised trial
- Comparison of omega-3 fatty acids and sulfasalazine in ulcerative colitis.2000 · Nutrition · Randomised trial
- Metabolic characteristics of healthy adult males as affected by ingestion of a liquid nutritional formula containing fish oil, oligosaccharides, gum arabic and antioxidant vitamins.1997 · Food Chem Toxicol · Randomised trial
- A randomized controlled study of evening primrose oil and fish oil in ulcerative colitis.1993 · Aliment Pharmacol Ther · Randomised trial
- Fish oil fatty acid supplementation in active ulcerative colitis: a double-blind, placebo-controlled, crossover study.1992 · Am J Gastroenterol · Randomised trial
- Treatment of ulcerative colitis with fish oil supplementation: a prospective 12 month randomised controlled trial.1992 · Gut · Randomised trial
- Supplementation with n-3 fatty acids from fish oil in chronic inflammatory bowel disease--a randomized, placebo-controlled, double-blind cross-over trial.1989 · J Intern Med Suppl · Study in people
- Omega-3 Fatty Acids and Balanced Gut Microbiota on Chronic Inflammatory Diseases: A Close Look at Ulcerative Colitis and Rheumatoid Arthritis Pathogenesis.2022 · J Med Food · Review
- Omega-3 fatty acids and inflammatory bowel diseases - a systematic review.2012 · Br J Nutr · Review
- Combining nutrition, food science and engineering in developing solutions to Inflammatory bowel diseases--omega-3 polyunsaturated fatty acids as an example.2010 · Food Funct · Review
- Fish oil for induction of remission in ulcerative colitis.2007 · Cochrane Database Syst Rev · Review
- Omega 3 fatty acids (fish oil) for maintenance of remission in ulcerative colitis.2007 · Cochrane Database Syst Rev · Review
- Eicosapentaenoic Acid-Acylated Astaxanthin Ameliorates DSS-Induced Chronic-Like Relapsing Colitis Associated With Gut Microbiota and Bile Acid Metabolism.2026 · Mol Nutr Food Res · In animals
- Combined Synbiotics and Omega-3 Polyunsaturated Fatty Acids Enhance Clinical and Histological Recovery in DSS-Induced Ulcerative Colitis: An Experimental Study in Rats.2026 · Diseases · In animals
- Effectiveness of probiotic- and fish oil-loaded water-in-oil-in-water (W1/O/W2) emulsions at alleviating ulcerative colitis.2024 · Food Funct · In animals
- Genomic analysis in the colon tissues of omega-3 fatty acid-treated rats identifies novel gene signatures implicated in ulcerative colitis.2024 · Int J Biol Macromol · In animals
- Eicosapentaenoic acid mitigates ulcerative colitis-induced by acetic acid through modulation of NF-κB and TGF-β/ EGFR signaling pathways.2023 · Life Sci · In animals
- Icosapent ethyl alleviates acetic acid-induced ulcerative colitis via modulation of SIRT1 signaling pathway in rats.2023 · Int Immunopharmacol · In animals
- Corrigendum to "Icosapent ethyl alleviates acetic acid-induced ulcerative colitis via modulation of SIRT1 signaling pathway in rats" [Int. Immunopharmacol. 115 (2023) 109621].2024 · Int Immunopharmacol · Other paper
- Perioperative parenteral fish oil supplementation improves postoperative coagulation function and outcomes in patients undergoing colectomy for ulcerative colitis.2022 · JPEN J Parenter Enteral Nutr · Other paper
- Omega-3 as a Part of the Dietary Guidance for Patients with Ulcerative Colitis: Beyond the Natural Sources.2021 · Clin Gastroenterol Hepatol · Other paper
- Short-term treatment with eicosapentaenoic acid improves inflammation and affects colonic differentiation markers and microbiota in patients with ulcerative colitis.2017 · Sci Rep · Other paper
