GLP-1 medications show comparable cancer risk to bariatric surgery, study finds

A large new study has found that people living with obesity and type 2 diabetes who are treated with GLP-1 receptor agonists have a similar risk of developing obesity-related cancers as those who undergo bariatric metabolic surgery.

The observational study, conducted in Israel using real-world health data from Clalit Health Services, compared outcomes in 6,356 adults treated between 2010 and 2018. Half received first-generation GLP-1 medications, a type of injectable drug increasingly used for weight and diabetes management. The other half underwent bariatric metabolic surgery, a proven intervention for obesity.

Over an average follow-up period of 7.5 years, researchers tracked the incidence of 13 types of obesity-related cancer, including colorectal, pancreatic, liver, kidney and postmenopausal breast cancer. Cancer rates were 5.62 cases per 1,000 person-years in the surgery group and 5.89 in the GLP-1 group – a statistically insignificant difference. The adjusted hazard ratio was 1.11 (95 per cent CI: 0.86–1.44), indicating no increased risk with GLP-1 use.

Researchers also explored whether weight loss alone accounted for the cancer risk reduction seen in both groups. Their analysis suggests that GLP-1 medications may offer protective benefits beyond weight loss, possibly through anti-inflammatory effects, although further research is needed to confirm these mechanisms.

The findings are likely to reassure patients and clinicians as GLP-1 medications such as liraglutide and semaglutide become more widely used in obesity care. While bariatric surgery remains a highly effective option, the results support GLP-1 RAs as a safe, non-surgical alternative in terms of long-term cancer risk.

Experts stress that more studies, including randomised controlled trials, are needed to fully understand the link between obesity treatments and cancer outcomes.