A study of more than 229,000 obese adults without diabetes in the United States showed that weight loss drugs were associated with a lower risk of obesity-related cancers.
The study found that GLP-1 receptor agonists (GLP-1 RAs), such as semaglutide (trade names: Ozempic, Wegovy) and tirzepatide (trade names: Mounjaro, Zepbound), were associated with a 41% lower overall risk of developing cancer in non-diabetic patients who used the drugs for weight management compared to those who relied on diet and exercise alone.
Published today (Monday) in a major cancer journal Oncology annual reportThis study is the first to examine the association between GLP-1 RA and obesity-related cancer incidence in people who are obese (BMI 30 or higher) but do not have diabetes. These patients tend to be younger than those with diabetes.
Thirteen cancers are associated with obesity and are known as obesity-related cancers. These include endometrial cancer, breast cancer, bowel cancer, kidney cancer, pancreatic cancer, thyroid cancer, ovarian cancer, esophageal cancer, stomach cancer, liver cancer, gallbladder cancer, multiple myeloma and meningioma. They account for approximately 40% of cancers diagnosed in high-income countries, and their incidence is increasing rapidly among young people.
“In our study, with an average follow-up of two years, GLP-1 “We found that RA use was associated with a significant reduction in the incidence of cancers directly caused by excess body weight. Overall cancer risk was reduced by 41%, and even greater reductions were seen in certain subgroups, including men, whose risk was almost reduced.” The incidence of endometrial cancer, one of the gynecological cancers most closely associated with obesity, was reduced by 70%.
“While the obesity-related cancer risk reduction in white patients was approximately 50%, this risk reduction was not observed in black patients. This may reflect additional causes such as access to care, differences in risk profile, and other biological differences.”
“We also studied various GLP-1 RA formulations and found that they all reduced the incidence of obesity-related cancers, but the greatest reduction was seen in tirzepatide users.”
GLP-1 RAs were originally developed to treat diabetes, but quickly became the most widely used drugs for weight loss. In the United States, use of GLP-1 RAs among obese, nondiabetic adults increased from approximately 21,000 patients in 2019 to more than 174,000 in 2023.
Dr. Kamat said, “While there was already evidence to suggest that these drugs may reduce cancer risk in people with diabetes, most people currently taking GLP-1 RAs for weight loss are not diabetic. They are young obese patients and represent a completely different population. “We wanted to investigate whether these drugs affect obesity-related cancer risk in this particular patient population, which makes up the majority of RA users. No one has studied this before.”
“GLP-1 RAs are already changing the way obesity is treated. What this analysis of more than 229,000 patients shows us is that their impact may be even broader and change the way we think about cancer prevention.”
Researchers analyzed records of 229,467 obese, non-diabetic patients extracted from a national database (TriNetX) covering 113 million patients in the United States. From December 2014 to June 2025, 86,422 (38%) patients received a prescription for a GLP-1 RA (semaglutide or tirzepatide) and 143,045 (62%) received advice on diet and exercise. They were followed for two years until they were diagnosed with cancer, died or were lost to follow-up, or from the time of their first drug prescription or dietary and exercise counseling. The mean age of the patients was 47 years.
After strictly matching GLP-1 RA patients with diet and exercise therapy patients to ensure a fair comparison between the two groups and emulate the conditions of a randomized controlled trial, each group included 80,899 patients, for a total of 161,796 patients.
“Our study suggests that GLP-1 RAs may have benefits beyond weight control,” said Professor Pedro Ramirez, the study’s second author and director of obstetrics and gynecology at Houston Methodist Hospital. “It should be noted that while the results of this study do not prove that GLP-1 drugs directly prevent cancer, they provide early evidence that merits further investigation in long-term clinical trials.”
Dr. Kamat said, “Given that our study showed a significant reduction in endometrial cancer incidence in GLP-1 RA users, we are currently investigating the mechanisms by which GLP-1 RA influences endometrial cancer growth and prognosis. We are studying the mechanistic pathways modulated by these drugs, a study that may open new therapeutic strategies for one of the most common gynecological malignancies.”
The researchers say their findings require further study, especially since the follow-up period was only two years. In the meantime, physicians and patients should consider the potential cancer prevention benefits when discussing the use of GLP-1 RAs.
“Our findings do not prove causation, and cancer risk reduction should not yet be the sole reason to prescribe GLP-1 RAs. However, for obese, nondiabetic patients who are already candidates for these treatments, our data provide an additional and potentially important reason to make that discussion,” Dr. Kamat said.
“For policy makers and other researchers, our study sends a clear signal that GLP-1 RAs deserve serious investigation as cancer prevention agents, especially as obesity-related cancers increasingly affect adults in their 40s and 50s.”
This study highlights the potential for a major shift in thinking about obesity treatment and cancer prevention. The use of GLP-1 RA therapeutics continues to increase worldwide, and understanding their broader health implications is critical. At Houston Methodist Hospital, we are committed to leading innovative, data-driven research that has the potential to improve patient outcomes far beyond the limits of traditional treatments. ”
Pedro Ramirez, professor of obstetrics and gynecology at Houston Methodist Hospital
sauce:
European Society of Clinical Oncology
Reference magazines:
Sue, A.H.-C. ,, others. (2026) GLP-1 receptor agonist use and cancer risk in obese non-diabetic adults. Oncology annual report. DOI: 10.1016/j.annonc.2026.04.013. https://linkinghub.elsevier.com/retrieve/pii/S0923753426001572.
