Popular daily supplement linked to increased stroke and heart disease risks

Woman holding fish oil supplements
-Credit: (Image: Getty Images)

Fish oil, long touted as a natural remedy for various health issues, might actually be linked to an increased risk of heart problems, according to recent research.

Despite being rich in Omega-3 fatty acids and commonly believed to benefit the brain, heart, and gut, a comprehensive study suggests that fish oil supplements could raise the likelihood of heart disease or stroke.

However, the study also indicates that for people already diagnosed with cardiovascular conditions, the consistent use of fish oil supplements may decelerate the progression of these ailments.

"Regular use of fish oil supplements might be a risk factor for atrial fibrillation and stroke among the general population," stated the researchers in their report, which was released on Tuesday in BMJ Medicine.

The investigation included 415,737 participants (55 percent of whom were women), aged between 40 and 69, all from the UK Biobanka vast database containing dietary, lifestyle, and health information of numerous Britons. These individuals were surveyed from 2006 to 2010 to gather foundational data, including their typical consumption of oily and non-oily fish, as well as fish oil supplements, the Mirror reports.

The research evaluated the potential impact of these supplements on the risk progression from good heart health to atrial fibrillation, leading to major cardiovascular events like heart attacks and, ultimately, death. Participants were divided and their health was monitored until March 2021 or until their demise, using data from medical records.

Man with heart disease
Fish oil was found to increase the risk of heart disease in some participants -Credit:Getty Images/iStockphoto

Almost a third (130,365; 31.5 percent) of the participants reported regular use of fish oil supplements. This group had higher proportions of older white individuals and women. The team noted that the group consuming more oily fish and alcohol also had fewer current smokers and residents in deprived areas.

The results suggested that regular use of fish oil supplements played varying roles in cardiovascular health, disease progression, and death.

For those with no known cardiovascular disease at the start of the monitoring period, regular use of fish oil supplements was associated with a 13 percent heightened risk of developing atrial fibrillation and a 5 percent heightened risk of having a stroke, according to a press release by the research team.

However, among those who had cardiovascular disease at the start of the monitoring period, regular use of fish oil supplements was associated with a 15 percent lower risk of progressing from atrial fibrillation to a heart attack, and a 9 percent lower risk of progressing from heart failure to death.

Taking a more in-depth look confirmed that risk factors such as age, sex, smoking habits, intake of non-oily fish, high blood pressure, and the use of statins and hypertension drugs all continue to raise risks for heart diseases, in addition to fish oil.

The team behind this observational investigation reminded us that, owing to its design, it's impossible to provide definitive conclusions about cause and effect. They also highlighted the absence of details regarding the dosage or type of supplement taken by subjects.

Despite these limitations, the research team noted: "Regular use of fish oil supplements might have different roles in the progression of cardiovascular disease. 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."

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