"Let’s get two facts out of the way: There's really no need to distinguish aluminum-free deodorants, because all deodorants are aluminum-free. (That said, we tend to conflate deodorant and antiperspirant—which does contain aluminum.) Many people like to use aluminum-free deodorants because they have heard it's safer, but every study to date suggests there is no definitive link between aluminum-based antiperspirant use and breast cancer.

Studies have shown that underarm 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."

The National Cancer Institute and leading scientists have called for large-scale epidemiological studies of the relationship between aluminum-based antiperspirants and the risk of breast cancer, but so far, no conclusive evidence has been found to label antiperspirants toxic. Our suggestion? Play it semi-safe: Switch to a deodorant on the days you shave, then use your aluminum-based antiperspirant on the days you don’t.

Looking for recs? These are the aluminum-free deodorants we love and trust for keeping our armpits dry and fresh. And if you're looking for the best natural and organic deodorants, we've got those too."

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