High doses of fish oil supplements, rich in omega-3 fatty acids, do not reduce a common type of irregular heartbeat known as atrial fibrillation, a new study, led by an Indian-origin scientist, has found.
In a trial led by the Montreal Heart Institute, 337 patients with atrial fibrillation not receiving conventional antiarrhythmic therapy were randomly assigned to four grammes of fish oil a day or to placebo for up to 16 months.
As many as 64.1 per cent of patients who had received fish oil experienced a recurrence of atrial fibrillation compared to 63.2 per cent of those taking placebo.
Furthermore, the study concluded that fish oil supplements did not reduce inflammation or oxidative stress markers, which may explain its lack of efficacy.
"Fish oil has no role in the rhythm-control management of atrial fibrillation," said lead investigator Dr Anil Nigam, Cardiologist at the Montreal Heart Institute and Associate Professor of Medicine at the University of Montreal.
"What is well-known and should be recommended to prevent heart disease and reduce blood pressure is a Mediterranean-type diet rich in natural omega-3 fats and other nutrients, including fresh fruits and veggies, legumes, olive oil, while lowering intake of red meat, trans fats and saturated fats," Nigam said.
"We believe that such a strategy might also be beneficial for the treatment of atrial fibrillation although more studies are required," said Nigam.
The risk of developing atrial fibrillation increases with age and with other risk factors such as obesity, diabetes, high blood pressure and underlying heart disease, researchers said.
The study was published in the Journal of the American College of Cardiology.
