Women who eat a lot of full-fat dairy like whole milk, cheese, and ice cream after being diagnosed with breast cancer may have a higher chance of dying sooner — and it seems to be because of the fat in these foods, not because one specific food is extra harmful.

If you’ve had breast cancer, eating a lot of full-fat dairy like whole milk, cheese, or butter might make you more likely to die from any cause — including things other than cancer — compared to eating only small amounts.

Eating dairy overall doesn’t seem to make breast cancer come back or kill more women from breast cancer, but it might be linked to dying from other causes — and that’s probably because the bad stuff (like full-fat dairy) is hiding in the average.

For women who’ve had breast cancer, eating a lot of full-fat dairy like whole milk, cheese, or butter might raise their risk of dying from other health problems like heart disease or diabetes—not from the cancer coming back.

If you’ve had breast cancer and eat a lot of full-fat dairy like whole milk or cheese every day, you might be more likely to die from breast cancer than if you eat only a little — possibly because the fat in dairy affects hormones that help cancer grow.

Eating dairy products like milk and cheese doesn’t seem to make breast cancer come back or kill more women from breast cancer, but people who eat a lot of dairy tend to die sooner from other causes — probably because of the fat in dairy, not the dairy itself.