Fish oil may increase the risk of heart disease and stroke, research shows

Fish oil supplements may increase a person’s risk of developing heart disease or stroke, but may reduce the risk for people who already have cardiovascular disease, according to research. research.

Fish oil is a rich source of omega-3 fatty acids. The NHS advises at least one portion of oily fish per week to help prevent the development of cardiovascular disease.

To find out how much protection it provides, a team of researchers in China, the US, Britain and Denmark monitored the health of more than 400,000 participants in the UK Biobank for an average of 12 years to estimate the associations between fish oil and fish oil. . supplements and new cases of atrial fibrillation (irregular heartbeat); heart attack, stroke and heart failure; and death in people without known cardiovascular disease.

They also assessed whether these supplements affected the progression of heart disease.

The study, published in the journal BMJ Medicine, found that in people without known cardiovascular disease at the start of the monitoring period, regular use of fish oil supplements was associated with a 13% increased risk of developing atrial fibrillation and a 5% increased risk. of a stroke.

But for patients with heart disease at the start of the study period, fish oil supplements were associated with a 15% lower risk of progressing from atrial fibrillation to heart attack, and a 9% lower risk of progressing from heart failure to death.

The benefits and risks of omega-3 supplementation were not uniformly observed, the study said. The risk that healthy patients would have a heart attack, stroke or heart failure was 6% higher in women and 6% higher in non-smokers.

There was also a greater beneficial effect for older people and men with existing heart conditions, with the risk of transitioning from good health to death being 11% and 7% lower respectively.

This was an observational study, so no conclusions can be drawn about causal factors, the authors caution. And no information was available about the dose or formulation of the fish oil supplements. Since most participants were white, the findings may not apply to people of other ethnicities, they add.

Tracy Parker, a senior dietitian at the British Heart Foundation, said: β€œThis research should not be a concern for people who regularly take fish oil supplements, but it is also not a green light to start taking them to prevent heart disease.

β€œIn Britain, the Nice guidelines do not recommend taking fish oil supplements to prevent cardiovascular disease or stop another heart attack. Supplements like omega-3 fatty acids are not a substitute for a healthy diet and rather than focusing on individual nutrients, it’s important to look at your diet as a whole to help lower your risk.

β€œThe traditional Mediterranean diet has been shown time and time again to reduce the risk of heart attack or stroke. This includes more fish – white and fatty – and less red meat, along with plenty of fruits and vegetables, beans, lentils, nuts, seeds and whole grains.”