Omega-3 supplements and heart health: the VITAL trial

What does the research say?

In this very large trial, taking 1 g of fish-oil omega-3 daily did not significantly reduce the main combined measure of heart attacks, strokes and cardiovascular deaths in generally healthy adults. There was a lower rate of heart attacks specifically — but that was a secondary result, so it needs confirming.

The science

Participants without previous cardiovascular disease or cancer were randomised to marine omega-3 fatty acids (EPA + DHA, 1 g/day), vitamin D, both, or placebo.

The primary cardiovascular endpoint — a composite of myocardial infarction, stroke and cardiovascular death — was not significantly reduced (HR 0.92). Among secondary outcomes, myocardial infarction was lower (HR 0.72), with larger apparent effects in people who ate little fish.

Key findings

• No significant reduction in the primary composite of major cardiovascular events.
• Fewer heart attacks in the omega-3 group (secondary outcome).
• Possible greater benefit in people with low fish intake (subgroup analysis).

Limitations

• Secondary and subgroup findings are hypothesis-generating, not conclusive.
• Tested a supplement, not oily fish — whole foods provide other nutrients too.
• Participants were generally healthy; results may differ in higher-risk groups.

References

1. Manson JE, Cook NR, Lee IM, et al. Marine n−3 fatty acids and prevention of cardiovascular disease and cancer. N Engl J Med. 2019;380(1):23–32. doi.org/10.1056/NEJMoa1811403