New research suggests that popular weight‑loss medicines might also help stop breast cancer. The study looked at more than 110,000 women and found that those who took GLP‑1 drugs were far less likely to get the disease.
What the Study Found
Scientists examined medical records from 111,646 women aged 45 to 80 who were overweight or obese. About 13.7% of them had prescriptions for GLP‑1 medicines such as Ozempic, Wegovy, Mounjaro or Zepbound.
When the researchers compared the women who used these drugs with those who did not, they saw a big difference. The drug users had roughly 30% lower odds of being diagnosed with breast cancer.
They repeated the comparison with a carefully matched group of 30,528 women. The result was the same – about a 30% reduction in risk.
Why These Drugs Might Help
GLP‑1 medicines copy a natural hormone that controls appetite and blood sugar. They are very good at helping people lose weight.
Carrying extra weight, especially after menopause, raises the chance of breast cancer. Losing weight can therefore lower that risk.
Beyond weight loss, the drugs also calm low‑grade inflammation and affect how genes work. Both of these actions could stop cancer cells from forming.
What Researchers Say
Dr. Elizabeth McDonald, a breast radiologist, explained that the study is observational. That means it shows a link, but it does not prove that the medicines cause the lower risk.
She added that the findings add to a growing body of evidence. “We want to test these drugs in a proper clinical trial to see if they can truly prevent breast cancer,” she said.
Future Research
Dr. McDonald’s team plans a large, multi‑site trial. The trial will enroll women who are at high risk for breast cancer, including some who have already had the disease.
The goal is to find out whether GLP‑1 medicines can be used as a prevention tool, not just for weight loss.
Current Prevention Options
Right now, women can lower their breast‑cancer risk with regular mammograms, MRI scans, preventive surgery, or medicines like tamoxifen. Many avoid tamoxifen because of side effects.
Because millions of people already take GLP‑1 drugs for diabetes or weight loss, they could become an attractive new option if future trials confirm the benefit.
The study was funded by the American College of Radiology Center for Research and Innovation, the Pennsylvania Breast Cancer Coalition, and the Abramson Cancer Center.