TAKE THAT, HATERS: GLP-1s REDUCE 14 Types of Cancer Risk in 86,000 Patient Study

What This New JAMA Oncology Study Really Means

Original posted at obesity.news/ on Aug 22, 2025

After a medicine is approved, the work does not stop. Post marketing studies look at how a drug performs in the real world, across many clinics and many kinds of patients, over much longer time frames than a trial. They use tools like electronic health records, claims data, registries, and sometimes simple pragmatic trials. The goal is to spot rare safety issues, confirm benefits outside of a narrow trial group, and find signals worth testing more deeply.

Today, using post-marketing data, there is fresh evidence that GLP-1 medicines may be lowering the risk of certain cancers. That is not a promise. It is a signal. But it is a hopeful one.

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What the study did

Researchers used electronic health records from OneFlorida plus, a large network that captures care across clinics and hospitals. They matched two groups of adults with obesity and no prior cancer history from 2014 through 2024. One group took a GLP-1. The other, though they would have qualified for them, did not. After careful matching, there were 43,317 GLP-1 users and 43,315 nonusers. This is called a target trial emulation, a way to make observational data behave more like a randomized study while still living in the real world.

Across 14 cancers, the GLP-1 group had fewer cancers overall. The incidence rate worked out to 13.6 per thousand person years for people on GLP-1s compared with 16.4 for those not on them. That maps to a hazard ratio of 0.83, which is a meaningful reduction. The clearest signals were in endometrial cancer, ovarian cancer, and meningioma. A small uptick for kidney cancer appeared, but it did not meet strong statistical certainty in this analysis.

If you prefer plain language, independent coverage framed it this way. A big real world look tied GLP-1 use to a lower chance of getting cancer, strongest in several women’s cancers, with a modest and uncertain nudge upward for kidney cancer that needs more study.

What this means if you are taking a GLP-1

You did not start a GLP-1 to prevent cancer. You started to treat obesity or diabetes and to reclaim your life. This study suggests there may be an added benefit on long term cancer risk, especially for women who carry the burden of endometrial and ovarian cancer risk with them. Hold that hope, and keep doing the daily work your body is asking you to do. Stay on your screening schedule. Keep your follow ups. None of that changes.

What this does not mean

It does not yet mean GLP-1s are cancer prevention drugs. It does not mean weight loss is the only reason for the signal, even though less visceral fat, lower insulin, and lower inflammation are very plausible pathways. Observational designs always leave room for unmeasured differences between groups. The authors themselves call for longer follow up and more research before changing guidelines. That is the right move.

Why this matters for our community

For years, people living with obesity have been told their disease raises cancer risk, then left without access to treatment. If GLP-1 therapy is lowering that risk while also improving diabetes, sleep apnea, and heart health, then access stops being a lifestyle debate and becomes a public health priority. That is not about vanity. That is about families, years of life, and the cost of care we carry together.

The bottom line

A careful analysis of more than eighty six thousand adults found fewer cancers among GLP-1 users, with the strongest drops in endometrial, ovarian, and meningioma cancers, and an uncertain signal for kidney cancer that needs more time and more data. The study does not prove causation and does not change screening or treatment today, but it adds weight to the idea that treating obesity with effective medicines can change long term health in ways that go far beyond a number on a scale.

Sources and further reading

Read the JAMA Oncology paper and abstract. Good journalism and expert reactions linked below add context on methods and limits.

JAMA Oncology abstract and methods. (JAMA Network)

PubMed entry. (PubMed)

Reuters Health Rounds summary. (Reuters)

AJMC write up. (AJMC)

Science Media Centre expert reaction. (sciencemediacentre.org)

Talk to me: Have you ever been told to just eat less and move more while your doctor ignored your cancer fears and your family history. Share your story in the comments. Tag someone who needs to hear that treatment for obesity is not about vanity, it is about survival. If you want the deep dive on endpoints and hazard ratios, I will post that in On The Pen later today along with a plain language Q and A on what these numbers do and do not mean.