Breaking down findings of new study on weight loss drugs and breast cancer

Added: 2026-06-03

[00:00:00]Researchers from Penn Medicine found that women taking the GLP-1 drugs like Wegovy and Zepbound were less likely to be diagnosed with breast cancer. Now, that sounds great. But we're hearing now there's so much more to it. Let's bring in our medical correspondent Dr. Celine Gounder. She's editor-at-large for public health at KFF Health News. Good morning to you, Celine. It was When I read this this morning, I thought, "This is really exciting." But I hear you going, "Wait, not so fast."

[00:00:23]>> [laughter] >> Not so fast.

[00:00:24]>> So, Penn Medicine looked at health records from over 100,000 women who had mammograms and other breast imaging.

[00:00:30]These 100,000 or more women were overweight, and about 15,000 of them were on GLP-1 drugs. And you'll hear this number 30% lower risk now. So, that sounds big until you look at the actual numbers. So, among women not on the drug, they 2.3% were diagnosed with breast cancer. Among those who were on the drug, 1.6%.

[00:00:53]So, it's a difference of less than 1%.

[00:00:55]math here matters.

[00:00:57]>> Mhm.

[00:00:57]>> Uh and so, you know, I don't I don't want people running home and thinking, "Oh, I need to be on a GLP-1 to prevent breast cancer." That is not the message at all here.

[00:01:06]>> But can we say that the drugs caused a difference in a positive way?

[00:01:10]>> We don't know. So, the women were not randomly assigned to the drug. They did not take into account many other factors that we know are predictive of whether somebody develops breast cancer or not. Some of that socioeconomic status, exercise, drinking, family history, genetic risk, really important one. What other drugs they were on.

[00:01:28]So, any of those other factors could actually explain why the group that were on the GLP-1s had a little bit lower rate of cancer. So, this is really a starting point to be asking questions, not definitive proof.

[00:01:40]>> And yet, these drugs are all over social media. I mean, it's blown up. This is a big conversation people are >> This is a really big conversation, and this I think what you tend to see on social media is extremes. Miracle drug, or "Oh, GLP-1s are unnatural and not good for you." And I do want to call out there was one oncologist from Stanford who posted on Instagram. I thought this was a really balanced comment. She said none of this data suggests people who do not have weight or endocrine issues should be taking GLP-1 drugs. And yet she was speaking optimistically about some of the results. So again, it's not a miracle drug. This is not necessarily bad for you. We just wait need to wait for more data.

[00:02:20]>> Adding some much needed perspective. Dr. Gupta, thank you. All right, coming up is the classic teen summer job disappearing? That's the question. We will find out