Let’s get two facts out of the way: There’s no such thing as an aluminum-free deodorant because all deodorants are aluminum-free, and every study to date suggests there is no definitive link between aluminum-based antiperspirant use and breast cancer.

Studies have shown that under-arm skin actually absorbs very little aluminum— only about 0.01 percent. But what about when you shave your armpits, then apply a swipe of antiperspirant? The absorption rate of aluminum goes up to 0.06 percent on pre-damaged skin, and a 2017 retrospective study “showed an earlier age of disease onset in breast cancer patients that had used aluminum-containing antiperspirants combined with underarm shaving.”