Everyday supplements › Fish Oil and the Heart › Studies

Does fish oil prevent heart disease?

Every study we read on this question

21 on-topic papers. Each has its own page: what it found, how much it counts, and how it fits.

The short answer

Little or no effect in most trials.

Confidence: moderate.

Read the full answer

Trials in people (14)

3.5-year trial in 1,228 dialysis patients: fish oil lowered serious heart events
Randomized trial20261,228 peoplePoints to benefit
Reanalysis of a trial in 25,871 older US adults: omega-3 lowered heart attack risk
Trial, not randomized202525,871 peoplePoints to benefit
Trial analysis in 8,175 adults: EPA drug lowered heart events, low or high LDL
Trial, not randomized20258,175 peoplePoints to benefit
Trial analysis in 7,026 adults: icosapent ethyl cut heart events regardless of lipoprotein(a) level
Trial, not randomized20247,026 peoplePoints to benefit
Trial in 2,460 adults in Japan: EPA did not clearly change main heart events
Randomized trial20242,460 peopleNo difference
Trial analysis in 8,179 adults by smoking history: icosapent ethyl lowered heart events
Trial, not randomized20238,179 peoplePoints to benefit
Trial subgroup of 1,837 adults with earlier bypass surgery: icosapent ethyl lowered heart events
Trial, not randomized20211,837 peoplePoints to benefit
Trial in 13,078 high-risk adults on statins: omega-3 did not clearly change heart events
Randomized trial202013,078 peopleNo difference
Trial in 8,179 adults on statins with high blood fats: EPA lowered heart events
Randomized trial20198,179 peoplePoints to benefit
Trial in 25,871 US adults: fish oil did not clearly change major heart events
Randomized trial201925,871 peopleNo difference
7.4-year trial in 15,480 adults with diabetes: omega-3 did not clearly change vascular events
Randomized trial201815,480 peopleNo difference
3-year trial in 2,157 older Europeans: omega-3 did not clearly change major heart events
Randomized trial20242,157 peopleNo difference
Trial analysis of 8,179 adults: similar heart benefit with or without irregular heartbeat history
Trial, not randomized20238,179 peoplePoints to benefit
Fish oil trial in 18,353 US adults over 50: heart events about the same
Randomized trial202118,353 peopleNo difference

Reviews (3)

Pooled review of 884 trials: omega-6 supplements were among those lowering heart risk factors
Pooled review (meta-analysis)2022883,627 peoplePoints to benefit
Pooled review of 86 trials found mixed results for fish oil and heart disease
Pooled review (meta-analysis)2020162,796 peopleMixed
Pooled review of 79 trials: no clear effect of fish oil on heart events
Pooled review (meta-analysis)2018112,059 peopleNo difference

Opinion (4)

Guideline for adults with high blood fats: EPA alone suggested, EPA plus DHA not
Other2025Mixed
Review of what past studies show about EPA and DHA and heart disease
Opinion or narrative review2023No direction
Review of past trials of fish oil in people with high blood fats
Opinion or narrative review2022No direction
Review of studies up to 2011 on omega-3 fats from fish and heart disease
Opinion or narrative review2011No direction