The reduced risk of heart disease seen in people who are overweight or have obesity taking the weight loss drug semaglutide may not be due to a drop in weight alone, a study shows. Researchers examined known risk factors for heart disease, such as body weight and waist circumference, in patients taking part in a clinical trial of semaglutide. Although the risk of serious cardiovascular disease was lower for those taking the drug, only half of this reduction could be explained by changes in these risk factors.The findings suggest that semaglutide may also be working to reduce heart disease in some other wa Growing popularity The use of weight loss medications known as GLP-1 receptor agonists, such as semaglutide, have become increasingly popular in recent years.Previous studies have shown that the drugs, used in the treatment of diabetes, are also effective in lowering cardiovascular disease risk in those who do not have the condition.A study led by the University of Edinburgh analysed data from more than 17,600 patients taking part in the SELECT trial to understand whether reductions in cardiovascular risk factors could fully account for the drop in heart disease. Heart health Half of the study participants were treated with semaglutide and half were given a placebo.The study examined whether factors like body weight, waist circumference and blood pressure changed over two years. They also examined any changes in blood tests, including cholesterol, and signs of diabetes, inflammation and kidney function. They compared this information with rates of cardiovascular disease, such as heart attack, stroke or death from cardiovascular disease, in the patients. Wider benefits Patients receiving semaglutide lost weight, had reduced waist measurements and improved blood tests. However, when researchers looked at all these factors separately and together, they could not fully account for the 20 per cent lower rates of heart disease in patients taking the treatment.Experts say further research is needed to explore how semaglutide could be preventing heart disease, but suggest the drug should be considered as a way of preventing serious cardiovascular disease, over and above its current use as a weight loss treatment. Whether we combine all risk factors together or look at some subsets of the risk factors, no more than half of the reduction in heart disease could be explained by the changes in these risk factors. These results suggest that semaglutide should be considered as a cardiovascular disease reduction drug and not just as a weight loss drug.We don’t know how else semaglutide could be preventing heart disease, but many other mechanisms have been proposed. These include anti-inflammatory effects not fully captured by the risk factors measured in the trial, and other direct effects on heart muscle or on the lining of blood vessels. Professor Helen Colhoun Study lead from the Institute of Genetics and Cancer The study, published in the European Heart Journal, was funded by and carried out in conjunction with the Novo Nordisk SELECT Trial Team and the SELECT Steering Committee. Related links Read the study in the European Heart Journal Helen Colhoun Research Page Tags 2026 This article was published on Thursday 24 September 2026
