Fish oil supplements for heart health may actually lead to higher risk of common heart rhythm disorder

SOPHIA ANTIPOLIS, France — Fish oil is the world’s most popular supplements, with many believing it’s vital for improving heart health. However, a new study finds they may actually be having the opposite effect. Researchers have discovered a link between fish oil and higher risks for the most common heart rhythm disorder — atrial fibrillation.

Study authors say people with high cholesterol are especially at risk. Even taking an over-the-counter omega-3 supplement may worsen their heart health, not improve it.

The global omega-3 supplement market size in massive, bringing in about $5.2 billion in 2019 alone. Around 19 million adults in the United States regularly take fish oil pills for their health.

Some trials suggest fishy fatty acids lead to atrial fibrillation, a quivering or irregular heartbeat resulting in poor blood flow. People with the disorder are five times more likely to have a stroke.

Researchers examined more than 50,000 people taking fish oils supplements or a placebo, following up on their health years later. The results show omega-3 fatty acid supplementation displays a link to a significantly increased risk for heart rhythm disorder in comparison to taking a placebo.

“Currently, fish oil supplements are indicated for patients with elevated plasma triglycerides to reduce cardiovascular risk,” says Dr. Salvatore Carbone from Virginia Commonwealth University in a media release. “Due to the high prevalence of elevated triglycerides in the population, they can be commonly prescribed. Of note, low dose omega-3 fatty acids are available over the counter, without the need for a prescription.”

The benefits of fish oil supplements are still in doubt

Fish oil was originally used during the Industrial Revolution to combat rickets, or a weakening of the bones. At the time, many youths suffered from low vitamin D levels in urban area with little sunlight.

In the early 1970s, Danish scientists discovered a link between the Inuit people of Greenland and low cardiovascular risk, suggesting this was due to them eating a lot of fish. However, this was later suggested to be an example of correlation, not causation.

Other studies point to omega-3 having benefits on memory, skin health, as well as having anti-inflammatory properties. However, a recent report on taking fish oil pills reveals their benefits may have more to do with an individual user’s genes rather than these supplements being a cure-all.

“Our study suggests that fish oil supplements are associated with a significantly greater risk of atrial fibrillation in patients at elevated cardiovascular risk,” Dr. Carbone concludes. “Although one clinical trial indicated beneficial cardiovascular effects of supplementation, the risk for atrial fibrillation should be considered when such agents are prescribed or purchased over the counter, especially in individuals susceptible to developing the heart rhythm disorder.”

The findings appear in the European Heart Journal – Cardiovascular Pharmacotherapy.

SWNS writer Joe Morgan contributed to this report.