Ozempic-Like Weight-Loss Drugs Linked to 30 Percent Lower Breast Cancer Risk: Study

A medication class widely used for weight management and type 2 diabetes may also hold promise for reducing breast cancer risk, according to new research presented at the 2026 American Society of Clinical Oncology Annual Meeting and published in JCO Oncology Practice.

Researchers analyzed health records of women aged 45 to 80 with overweight or obesity who underwent breast imaging between 2022 and 2025. They found that women who had been prescribed these medications were significantly less likely to develop breast cancer than those who had not used them.

The study included more than 111,000 women, of whom about 14% had received the treatment. After comparing breast cancer diagnoses between users and non-users, researchers observed a substantially lower likelihood of breast cancer among women taking the medications.

Scientists say the findings add to growing evidence that these medications may influence cancer risk through more than just weight loss. Excess body weight, particularly after menopause, is a well-established risk factor for breast cancer. However, researchers believe other mechanisms may also contribute. The drugs are known to reduce chronic inflammation, improve metabolic health, and affect biological pathways involved in cell growth and gene regulation—all factors that may play a role in cancer development.

Despite the encouraging results, researchers caution that the study was observational and cannot prove that the medications directly prevent breast cancer. Important factors such as duration of treatment, genetic risk, tumor subtype, and cancer stage were not evaluated.

Researchers are now planning larger clinical trials to determine whether these medications can actively reduce breast cancer risk in women considered at high risk for the disease.

If confirmed, the approach could offer a new avenue for breast cancer prevention alongside screening and existing risk-reduction strategies.

REFERENCE: Elizabeth S. McDonald, Laura B. Gillis, Peter Gabriel, Kham Xapakdy, Anthony Young, Abigail Doucette, Mitchell D. Schnall, John B. Buse, Etta D. Pisano. GLP-1 Agonists Are Associated With a Significant Reduction in Breast Cancer Incidence in Women. JCO Oncology Practice, 2026; DOI: 10.1200/OP-26-00485