What does science say about Omega-3 fatty acids (fish oil) and cancer (all types)?
- We don’t say yes or no. We show what has been studied.
- Working in a lab or in animals does not mean it works in people.
- Don’t stop or change your treatment without talking to your doctor.
What has been studied
- Lab studies (cells)Tests on cells in a dish.Source: PubMed · as of 12 Nov 2026 · Open the search at PubMed258studies
- Animal studiesTests in mice, rats or other animals.Source: PubMed · as of 12 Nov 2026 · Open the search at PubMed329studies
- Studies in peoplePublished studies with human participants.Source: PubMed · as of 12 Nov 2026 · Open the search at PubMed262studies
- Registered trials in peopleTrials entered in a public registry, whatever their result.ClinicalTrials.gov: 20 · as of 12 Nov 2026 · Open the search at ClinicalTrials.govEU CTIS: 0 · as of 12 Nov 2026 · Open the search at EU CTISBy phase:No phase (14)Phase 2 (2)Phase 3 (2)Phase 1/2 (1)Phase 4 (1)By status:Recruiting (9)Completed (4)Not yet recruiting (2)Running, not recruiting (2)By invitation only (1)Withdrawn before start (1)Stopped early (1)Countries (9):United States (5)China (2)Denmark (2)Spain (2)United Kingdom (2)Mexico (2)Canada (1)Egypt (1)South Korea (1)With a linked publication (results): 3 of 20The registries do not tell us here whether results were posted; a linked publication is shown instead.20trials
- Approved treatmentApproved by a medicines regulator for this disease.No
Cancer here means all 33 cancer types we cover.
Examples of what we found
The trials
No phase
Immunonutrition for Surgical Prehabilitation of Patients With Upper GI Cancer
By invitation only · Spain
ClinicalTrials.gov · NCT07884214Phase 2
Omega-3 Supplementation and Immunotherapy in Gastric Cancer: A Phase II Trial
Not yet recruiting · China
ClinicalTrials.gov · NCT07050524No phase
Omega-3 Fatty Acids With PD-1 Inhibitors in Advanced Esophageal Cancer
Recruiting · China
ClinicalTrials.gov · NCT07272382No phase
Nutritional Therapy Enriched With Omega-3 in Patients With Lung Resection
Recruiting · Mexico
ClinicalTrials.gov · NCT06531460No phase
Prevention of Oxaliplatin-induced Nerve Damage in the Body's Extremities
Recruiting · Denmark
ClinicalTrials.gov · NCT05404230Phase 2
Phase II Trial to Modulate Intermediate Endpoint Biomarkers in Former and Current Smokers
Running, not recruiting · United States
ClinicalTrials.gov · NCT03598309Phase 3
EPA for Metastasis Trial 2
Running, not recruiting · United Kingdom
ClinicalTrials.gov · NCT03428477No phase
Omega-3 Fatty Acid and Colorectal Adenoma
Completed · South Korea
ClinicalTrials.gov · NCT06427109No phase
Prebiotic Effect of Eicosapentaenoic Acid Treatment for Colorectal Cancer Liver Metastases
Completed · United Kingdom
ClinicalTrials.gov · NCT04682665No phase
Effect of an Anti-inflammatory Diet on Patients With Cervical Cancer
Completed · Mexico
ClinicalTrials.gov · NCT03994055
Thinking of paying for it? Read this first
- Ask for published results. Stories, thank-you letters and "patients report" are not results. Ask where the results were published.
- Know what you pay for. Ask in writing: what exactly is included, who gets the money, and what happens if you stop.
- Ask your own doctor first. Some products interfere with chemotherapy, radiation or other medicines. Your treating doctor can check this.
- Do not stop standard treatment for it. Do not stop or delay your treatment without talking to your care team.
Not medical advice. Talk to the care team before changing treatment.