Individuals who regularly use fish oil supplements are at risk of being diagnosed with a heart condition or having a stroke, a new study has claimed.

However, those who already have cardiovascular disease can prevent further heart complications from developing by using fish oil supplements, the research has suggested.

Fish oil is one of the most commonly consumed dietary supplements that are rich in omega-3 fatty acids.

To prevent the development of cardiovascular disease, people should be eating at least one portion of oily fish a week, according to the NHS.

During the investigation, a team of international researchers analysed the health outcomes of more than 400,000 adults in the UK Biobank to assess the impact of fish oil.

They looked at whether fish oil supplements triggered new cases of atrial fibrillation (irregular heartbeat), heart attack, stroke, heart failure and death in people with no known cardiovascular disease.

The results have shown that the participants with no known cardiovascular disease at the start of the study were 13% more likely to develop atrial fibrillation and 5% more at risk of having a stroke if they regularly use fish oil supplements.

However, those with heart disease at the beginning of the study were 15% less likely to have a heart attack if they frequently use fish oil supplements.

Dietitian Tracy Parker said: “This research shouldn’t be concerning to people who regularly take fish oil supplements, but it’s also not a green light to start taking them to prevent heart and circulatory diseases.

“In the UK, NICE guidelines don’t recommend taking fish oil supplements to either prevent heart and circulatory diseases or stop another heart attack.”

She added: “Supplements such as omega-3 fatty acids are no substitute for a healthy diet and, instead of focusing on individual nutrients, it’s important to look at your diet as a whole to help lower your risk.

“The traditional Mediterranean diet has been shown time and again to reduce the risk of heart attack or stroke.

“This includes more fish – white and oily – and less red meat, along with plenty of fruit and vegetables, beans, lentils, nuts, seeds and wholegrains.”

The study has been published in the journal BMJ Medicine.

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