Fish oil supplements may increase heart disease, stroke risk: study

Tracy Swartz
·3 min read
Regular use of fish oil supplements might increase the risk of developing heart disease or having a stroke for the first time — but it also might slow the progression of existing cardiovascular health problems and lower the risk of death, a new UK study finds.
Regular use of fish oil supplements might increase the risk of developing heart disease or having a stroke for the first time -- but it also might slow the progression of existing cardiovascular health problems and lower the risk of death, a new UK study finds.

Time to scale back?

Steady use of fish oil supplements might increase the risk of developing heart disease or having a stroke for the first time — but it also might slow the progression of existing cardiovascular health problems and lower the risk of death, a new UK study finds.

“Regular use of fish oil supplements might be a risk factor for atrial fibrillation and stroke among the general population,” the study authors wrote in their findings, published Tuesday in the journal BMJ Medicine.

Regular use of fish oil supplements might increase the risk of developing heart disease or having a stroke for the first time — but it also might slow the progression of existing cardiovascular health problems and lower the risk of death. Getty Images
Regular use of fish oil supplements might increase the risk of developing heart disease or having a stroke for the first time — but it also might slow the progression of existing cardiovascular health problems and lower the risk of death. Getty Images

“But [it] could be beneficial for progression of cardiovascular disease from atrial fibrillation to major adverse cardiovascular events, and from atrial fibrillation to death,” they added.

Fish oil is rich in omega-3 fatty acids, which have been shown to support brain and heart health.

But studies on the benefits of fish oil supplements have yielded mixed results.

The leading cause of death worldwide, cardiovascular disease includes heart failure, heart attacks and strokes. Getty Images
The leading cause of death worldwide, cardiovascular disease includes heart failure, heart attacks and strokes. Getty Images

For this latest research, the study authors tracked the health of 415,737 people 40 to 69 years old for about 12 years.

Some 31.5% of the participants (130,365) said they regularly took fish oil supplements.

The supplements were linked to a 13% higher risk of developing atrial fibrillation — an irregular heartbeat — and a 5% elevated risk of having a stroke for those who had no history of cardiovascular disease.

The leading cause of death worldwide, cardiovascular disease includes heart failure, heart attack and stroke.

Further studies are needed to explore the link between fish oil supplements and cardiovascular disease risk, the researchers said. Getty Images
Further studies are needed to explore the link between fish oil supplements and cardiovascular disease risk, the researchers said. Getty Images

For those who did have one of these conditions before participating in the study, fish oil supplementation was associated with a 15% lower risk of their atrial fibrillation progressing to a heart attack and a 9% lower risk of dying after heart failure.

The risk of transitioning from good health to heart attack, stroke or heart failure was 6% greater for female and non-smoking supplement takers.

Men and older people were better able to reap the rewards of the supplements, reducing their risk of progressing from good health to death by 7% and 11%, respectively.

The researchers noted that information about the dose and formulation of the fish oil supplements taken by participants was not available for their study.

And most of the participants were white, so the findings might not apply to people of other ethnicities.

“Further studies are needed to determine the precise mechanisms for the development and prognosis of cardiovascular disease events with regular use of fish oil supplements,” the study authors wrote.