Omega-3 supplements are widely touted for their blood-thinning effects, making them useful to ward off cardiac events. But research is conflicting, as some studies suggest the supplements have little to no effect on the risk of heart disease. A new body of research has raised questions over the safety of the pill at higher doses. According to the findings, high-dose omega-3 supplements could increase the risk of AF by up to 50 percent.
The findings of the 2021 report, published in the journal Circulation, suggested patients prescribed higher doses could be at potential risk for AF.
The meta-analysis included seven large-scale randomised clinical trials of the marine omega-3s.
Four of the trials tested relatively low doses of marine omega-3s, while another three tested high-dose omega-3s.
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Together, the trials included more than 81,000 participants and found that the risk of AF was elevated 1.25-fold with the omega-3s.
Medscape summarises the findings with the statement: “The trials had tested lower doses and, individuals, they did not show a significant increase in AF.
“In high-dose trials, there was a 49 percent – 50 percent risk. In a dose-response gradient analysis, for each one-gram increase in the dose of the omega-3s, there was an 11 percent increase in the risk for AF – a strongly significant interaction.”
The study also found evidence that higher doses of omega-3s were associated with a lower risk for cardiovascular events, of around nine percent.
More research is needed to elucidate the risks of taking omega-3 supplements, how this may vary by formation or dose, or how it fits into the benefit-risk ratio.
There is a general consensus that omega-3s do not confer protection against stroke, which was confirmed by all bar one trial.
This led researchers to question whether the absence of omega-3 benefits for stroke risk could be due to the link between AF and stroke.
This is because having AF increases the risk of stroke by five times, according to the health association Stroke.
It comes as a recent study has claimed rates of AF are at an all-time high, with documented growth of 72 percent over the past two decades.
According to the findings, the prevalence of AF now outnumbers the four most common cancer.
Professor Sir Nilesh Samani, British Heart Foundation Medical Director, said detection measures needed to be improved so more people could benefit from anti-clotting drugs.
The expert noted: “The sheer rise in the number of people now living with AF is staggering, and yet on top of this, many more people will be unaware that they also have this hidden stroke risk in their heart.”
Any heart-healthy diet should emphasise fruits, vegetables, wholegrain and plant-based protein sources like beans, but evidence suggests potassium-rich foods offer special benefits for the prevention of AF.
WebMD states: “Research shows that if your blood is low in potassium, you are at higher risk for AF.”
Dipping the head in cold water can also stimulate the vagal nerve, which in turn can slow the heart.
Taking deep breaths, doing acupuncture, and taking magnesium supplements have also been found to benefit the heart.