Women Taking This Medication Had A 56% Lower Recurrence Of Breast Cancer
Breast cancer is the most common cancer among women in the U.S., making up more than 30% of all cases. And people who are also managing obesity or type 2 diabetes are at higher risk of complications (including the cancer coming back).
Now, a large study1 suggests that GLP-1 medications, the drug class that includes semaglutide (Ozempic, Wegovy) and tirzepatide (Mounjaro, Zepbound), may offer real benefits for breast cancer survivors who have these metabolic conditions. Here's what you need to know.
About the study
Researchers wanted to better understand whether taking a GLP-1 was associated with breast cancer outcomes in women with obesity or diabetes.
Researchers looked at health records from more than 841,000 women with stage I to III breast cancer across 68 U.S. health care organizations. They compared outcomes for people who used GLP-1 medications versus those who didn't, as well as those taking other diabetes drugs like insulin, metformin, or SGLT2 inhibitors.
The researchers specifically looked at:
- All-cause mortality (risk of death from any cause)
- Recurrence-free survival (whether the cancer returned)
Patients were followed for up to 10 years.
The benefits of GLP-1 use
Women with breast cancer who were taking GLP-1 medications tended to have better long-term outcomes, especially those with obesity or type 2 diabetes.
- For people with obesity GLP-1 use was associated with a 65% lower risk of death and a 56% lower risk of cancer recurrence over 10 years compared to nonuse.
- For people with type 2 diabetes, GLP-1 use was associated with a 91% lower risk of death and a 67% lower risk of recurrence compared to insulin or metformin use.
When researchers compared GLP-1s to SGLT2 inhibitors (another newer diabetes drug class), they didn't see significant differences, suggesting both may offer similar benefits.
For women with obesity using GLP-1s, survival rates were 97.4% at 5 years and 96.0% at 10 years, compared to 93.2% and 88.6% for non-users.
Why obesity affects breast cancer outcomes
The link between carrying extra weight and cancer risk is well established. Obesity creates conditions in the body that can help tumors grow, including ongoing inflammation, insulin resistance (when your cells don't respond well to insulin), and higher estrogen levels (since fat tissue produces estrogen).
For breast cancer specifically, having obesity at diagnosis or gaining weight during treatment is tied to higher recurrence rates and lower survival.
How GLP-1s might help
GLP-1 medications were originally developed for type 2 diabetes and later approved for weight loss. Their potential benefits for cancer survivors likely go beyond the scale:
- Weight loss: GLP-1s support weight loss, which may reduce the metabolic factors that worsen cancer outcomes.
- Better blood sugar control: GLP-1s improve insulin sensitivity means less of the insulin resistance that can fuel tumor growth.
- Heart protection: GLP-1s have proven heart health benefits, and heart disease is a leading cause of death among breast cancer survivors.
- Possible direct effects: Some early preclinical research suggests GLP-1 signaling may directly influence tumor biology, though this area is still preliminary and far from proven in humans.
What we still don't know
This was an observational study, not a clinical trial, so it can't prove that GLP-1s directly caused the better outcomes. A few things could be influencing the results:
- The "healthy user" effect: People who get GLP-1 prescriptions may have better access to health care, more regular checkups, and be more proactive about their health overall.
- Timing matters: GLP-1 prescribing has increased in recent years, which overlaps with general improvements in breast cancer treatment.
- What kind of deaths? The study measured death from any cause, not just breast cancer. Since GLP-1s help protect the heart, some of the survival benefit may come from fewer heart-related deaths rather than direct cancer effects.
The researchers are calling for clinical trials to better understand the potential risks and best timing for GLP-1 therapy in breast cancer survivors.
What survivors can do now
If you're a breast cancer survivor with obesity or type 2 diabetes, this research adds to growing evidence that metabolic health matters for cancer outcomes.
While GLP-1s aren't approved specifically for cancer treatment, they may be worth discussing with your care team if you're already a candidate for weight management or diabetes treatment.
Some questions to ask your oncologist or primary care provider:
- Would a GLP-1 medication make sense for my metabolic health goals?
- How might weight management affect my cancer treatment or long-term outcomes?
- What metabolic markers should we be tracking?
Lifestyle habits that support metabolic health
Whether or not medication is part of your plan, lifestyle factors remain the foundation for both metabolic health and cancer survivorship:
- Build and maintain muscle: Strength training and eating enough protein support metabolic health and have been linked to better cancer outcomes.
- Eat to reduce inflammation: A diet rich in vegetables, fruits, whole grains, and omega-3 fatty acids can help calm chronic inflammation.
- Stay active: Regular movement improves how your body handles blood sugar, supports a healthy weight, and has its own benefits for cancer survivors.
- Talk to your care team: Metabolic health is increasingly seen as part of comprehensive cancer care, and it's important to talk to your provider about what your options are for weight management.
The takeaway
This new, large study found that GLP-1 medications were linked to significantly better survival and lower cancer recurrence among breast cancer survivors with obesity or type 2 diabetes. While clinical trials are needed to confirm these findings, the research suggests that metabolic health plays an important role in cancer outcomes, and that GLP-1 medications may offer benefits beyond weight loss and blood sugar control.