A study drawing on the electronic health records of more than 160,000 obese adults without diabetes has found that those prescribed GLP-1 receptor agonists had a 41 per cent lower risk of developing 13 obesity-related cancers compared with patients who lost weight through diet and exercise alone. The research, led by National Taiwan University Hospital and published in Annals of Oncology, used propensity-score matching to compare outcomes over an average follow-up of about two years. The greatest reductions were observed for endometrial and colorectal cancers, while no significant difference emerged for breast cancer.

The finding adds to a flurry of observational evidence suggesting that the class of drugs, which includes semaglutide and tirzepatide, may confer benefits beyond weight reduction. A separate study published in The BMJ, involving nearly 53,000 type 2 diabetes patients with established heart disease, reported that those receiving tirzepatide (Mounjaro) were 33 per cent less likely to suffer a heart attack than patients on sitagliptin, with major adverse cardiovascular events occurring in 2.9 per cent of the tirzepatide group versus 4.4 per cent after one year. Meanwhile, an analysis of almost 134,000 Americans aged 50 to 90 with type 2 diabetes, published in JAMA Network Open, linked GLP-1 agonists to a 21 per cent lower risk of low-trauma fractures over three years, with the most pronounced reductions in hip, femur and spine fractures.

All three studies are retrospective and rely on real-world prescribing data, meaning they cannot demonstrate a direct causal effect. The Taiwan team stressed that their results do not constitute a new approved indication for GLP-1 drugs and that the findings must be confirmed in prospective clinical trials. The fracture study’s authors similarly underlined the observational design, noting that earlier concerns had centred on the possibility that rapid weight loss might weaken bones. The next milestone will be the publication of randomised controlled trials designed to test whether these protective signals hold up under rigorous prospective conditions.