Omega-3: what the evidence actually shows

declining omega-3 — attention cooling after large mixed/null trials

Reviewed by Substrate editorial, Independent research collective · 2026-03-20

⚠ Safety in context

seriouswith Warfarin: High-dose omega-3 with warfarin may increase bleeding risk.

Evidence by outcome

heart healthgrade Bmoderate certainty— modest cardiovascular benefit; large recent trials were mixed

inflammationgrade Bmoderate certainty— lowers circulating inflammatory markers (CRP, IL-6) dose-dependently

joint healthgrade Bmoderate certainty— reduces joint tenderness / morning stiffness in rheumatoid arthritis

moodgrade Cmoderate certainty— small benefit for depressive symptoms, clearest with higher-EPA formulations

cognitionnot well studiedvery-low certainty— not adequately studied for cognition in healthy adults

People say · Evidence shows

“Fish oil prevents heart attacks”

aheadlargemarketing claim

Grade history

2026-03-20B → BA large cardiovascular outcomes trial missed its primary endpoint; state softened to mixed. details →

Re-review cadence: every 12 months (Grade A/B) · next scheduled by 2027-03-20 · methodology v1.

By outcome — the money pages

sources: PMID:20000103 · PMID:41886199 · PMID:20000102

Cite this page

Reuse under CC-BY 4.0 with attribution to evidencebased.info.

Plain-text citation

Substrate. Omega-3: what the evidence actually shows. https://evidencebased.info/interventions/omega-3. Updated 2026-03-20.

BibTeX

@misc{substrate_ointerventionsomega3,
  author = {Substrate editorial},
  title  = {Omega-3: what the evidence actually shows},
  year   = {2026},
  url    = {https://evidencebased.info/interventions/omega-3},
  note   = {evidencebased.info}
}