The weight-loss drug semaglutide – the active ingredient in Wegovy – significantly reduces the risk of heart attack and stroke, regardless of how much weight a person loses, according to the largest study of its kind.
Published in The Lancet, the UCL-led trial analysed data from 17,604 adults aged 45 and older who were overweight or obese. Half received weekly semaglutide injections, while the rest were given a placebo. Researchers found that semaglutide users were 20% less likely to suffer a major cardiac event such as a heart attack, stroke, or heart disease death.
Importantly, the heart benefits appeared independent of weight loss, with even mildly overweight participants (BMI around 27) experiencing similar improvements to those with higher BMI.
However, shrinking waistlines did correlate with better heart outcomes. About one-third of the benefit was linked to reduced waist circumference — a sign of less abdominal fat, which is particularly harmful to cardiovascular health.
Lead author Prof John Deanfield said: “Abdominal fat is more dangerous than overall weight, but our findings show two-thirds of the heart benefit can’t be explained by fat loss alone. This reframes how we view these drugs — they’re not just weight-loss treatments but medications that directly affect heart health.”
Deanfield added that restricting semaglutide only to patients with the highest BMI “doesn’t make sense” if the goal is to prevent cardiovascular disease, though he stressed the need to balance benefits with potential side effects as its use expands.
