Taking fish oil supplements doesn’t seem to lower your risk of having a heart attack or other heart disease, according to this review of many clinical trials.
Scientific Claim
Supplementing with long-chain omega-3 polyunsaturated fatty acids shows no significant reduction in coronary disease risk (RR: 0.94, 95% CI: 0.86–1.03) based on 27 randomized trials.
Original Statement
“In randomized, controlled trials, relative risks for coronary disease were ... 0.94 (CI, 0.86 to 1.03) for long-chain ω-3 polyunsaturated fatty acid supplementations.”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
association
Can only show association/correlation
Assessment Explanation
The claim correctly uses 'shows no significant reduction' and reports the exact effect size and CI. Although RCTs can suggest causation, the result is non-significant, so association language is appropriate.
Evidence from Studies
Supporting (1)
Association of dietary, circulating, and supplement fatty acids with coronary risk: a systematic review and meta-analysis
This big study looked at 27 experiments where people took omega-3 supplements and found no clear benefit in preventing heart disease — the numbers show the supplements didn’t make a meaningful difference.