Regular use of fish oil supplements may be linked to lower risk of death and cardiovascular disease (CVD), according to research in UK patients.
Further studies should investigate what dose is required to have a clinically meaningful effect, said the researchers behind the study published in the British Medical Journal.
“Habitual use of fish oil appears to be associated with a lower risk of all causes and CVD mortality.”
They found that fish oil was a popular dietary supplement in the UK, with some evidence suggesting that omega-3 fatty acids, although inconclusive, may help prevent CVD and reduce mortality.
To further explore these potential associations, researchers in China and the United States examined data from the UK Biobank, a large population-based study of more than half a million British men and women.
Their analysis included 427,678 men and women between the ages of 40 and 69 years without CVD or cancer who were enrolled in the study between 2006-10 and who completed a survey on dietary supplement use.
Death certificates and hospital records were used to monitor all cause deaths, CVD deaths, and CVD events such as heart attack and stroke through 2018.
Almost a third – 31% – of the participants said they took fish oil supplements regularly at the start of the study, the researchers said.
They found that fish oil supplements were associated with a 13% lower risk of all-cause mortality, a 16% lower risk of CVD mortality, and a 7% lower risk of CVD events.
This corresponded to 388 fewer deaths from all causes, 124 fewer CVD deaths and 295 fewer CVD events per 100,000 people over a mean follow-up period of nine years.
The study authors found that the association between fish oil consumption and CVD events appeared to be stronger in patients with high blood pressure.
Several mechanisms could explain these results, the authors said – for example, omega-3 fatty acid supplements have shown beneficial effects on blood pressure, cholesterol levels, and heart rate.
They concluded that habitual fish oil use was “associated with a lower risk of all-cause and CVD mortality and a marginal benefit for CVD events in the general population”.
Future studies are needed to investigate how the dose of fish oil supplements affects the ability to produce a “clinically meaningful effect,” they added.