TV doctor Dr Amir Khan, a regular on ITV's This Morning and Lorraine, has spoken out after research suggested that fish oil supplements might increase the risk of developing a serious heart condition. The study, involving over 400,000 UK patients, prompted Dr Khan to ask whether people should stop taking these pills, which are used by an estimated 20 million Britons.
Study Findings on Fish Oil and Heart Risk
Fish oil, rich in omega-3 fatty acids, is often recommended to prevent cardiovascular disease. However, new research published in BMJ Medicine by scientists from Sun Yat-Sen University in China found that healthy individuals who regularly take fish oil supplements may face a higher risk of stroke or atrial fibrillation (AF), an abnormal heart rhythm. The study followed over 400,000 British people for an average of 12 years, with nearly a third (130,365) reporting regular use of fish oil supplements.
Results showed that healthy participants who used fish oil regularly were 13% more likely to develop atrial fibrillation and 5% more likely to have a stroke compared to non-users. Conversely, for those with pre-existing heart conditions, the supplements appeared to reduce the risk of further heart issues.
Dr Khan's Instagram Explanation
Addressing his Instagram followers, Dr Khan said: "You may well have seen the headline saying fish oil causes atrial fibrillation. So, should we all stop taking our omega-3 supplements? Well, the answer is a bit more complicated than that." He noted that the study only showed an association, not causation, and lacked details on dosage, type of fish oil, or consistency of use. However, he acknowledged that this is not the first study to raise concerns.
Dr Khan referenced large randomized control trials that found a "consistent signal" linking high-dose fish oil supplements to increased AF risk. "Several analyses have shown around a 25% increase in relative risk overall, and the risk seems to rise as the dose goes up," he said. He highlighted that prescription-strength omega-3 products (2 to 4 grams daily) pose the highest risk, with European regulators recognizing a dose-dependent AF risk, peaking at about 4g per day.
Perspective and Practical Advice
Dr Khan urged calm, emphasizing that the absolute risk increase is small and primarily concerns high-dose marine omega-3 supplements (EPA and DHA). For standard over-the-counter capsules, the evidence is less clear. Importantly, omega-3 from food sources does not show the same risk. "Eating oily fish is still recommended as part of a healthy balanced diet," he said, noting that studies have found lower AF rates in people with higher natural omega-3 levels.
His take-home message: "If you're taking a fish oil supplement because you think it's a magic bullet for your heart health, the evidence really isn't there. If you're taking high-dose omega-3 under medical supervision for a specific reason, discuss it with your doctor. But for most people, you're probably better off getting your omega-3 from food—oily fish, or plant sources like walnuts, flax seeds, and chia seeds."
Dr Khan concluded: "The strongest evidence still supports focusing on your overall lifestyle: a healthy diet, staying active, getting enough sleep, not smoking, and managing conditions like high blood pressure and diabetes. A Mediterranean-style diet with oily fish remains one of the best approaches for reducing heart attack and stroke risk."
