Omega-3 fatty acids do not decrease death risk from heart attack or cancer

Omega-3 fatty acids do not decrease death risk from heart attack or cancer, according to a new study.

It is a widespread belief that omega-3 fatty acid supplements are associated with reduced risks of cardiovascular disease and cancer. However, a recent study published in the New England Journal of Medicine has found that omega-3 supplementation did not result in a lower incidence of cardiovascular disease or cancer than placebo.

The VITAL randomized trial provides fresh evidence to support current recommendations that omega-3 fatty acid supplements in usual doses should not be offered for the prevention of cardiovascular disease. It also provides new evidence that they do not reduce the risk of cancer. This may not be the end of the story though as other research into other doses exists.

Several observational studies have associated higher intake of omega-3 fatty acids with reduced risks of cardiovascular disease and cancer. However, trials testing the effect of various doses of omega-3 fatty acid supplementation on cardiovascular disease outcomes or cancer risk have shown inconsistent results.

JoAnn E. Manson, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, and colleagues conducted this study to address this knowledge gap. It also looked at whether Vitamin D reduced either risk, though the results are reported in a separate paper.

The trial studied 25,871 men and women in the United States and compared the association between 1g a day of omega-3 fatty acid supplements versus placebo on major cardiovascular events and invasive cancer. The results are in akin to a recent Cochrane review that assessed effects of increased intake of fish‐ and plant‐based omega‐3 for all‐cause mortality, cardiovascular (CVD) events, adiposity and lipids.