The magical juice that can be used to ward off body odor? Lemon. Ellen Marmur, an associate clinical professor of dermatology at Mount Sinai Medical Center, confirmed that lemon juice can, in fact, be useful as a natural deodorant because the citric acid in it kills bacteria and odor. To be clear, it won't really help when it comes to keeping you dry, though. "Antiperspirants, even natural ones, physically block sweat glands a bit. You don't get that from lemon juice," says Marmur.
Speaking of antiperspirants, we should make the distinction between deodorants and antiperspirants, in case you're still not sure. "Deodorants are cosmetic products that only deal with eliminating or masking odor," explains cosmetic chemist Jim Hammer. "Antiperspirants are over-the-counter pharmaceutical products containing an active ingredient, like aluminum chlorohydrate, and are used to stop the wetness, as well." Most of the big brands you see in drugstores are antiperspirants, but an impressive number of natural options have been popping up in those same aisles, and many of them are deodorants.
"Lemon juice has mild astringent effects that mimic the pore-closing effect of antiperspirant actives," says Hammer. "And the lemon scent is also useful
for covering malodors—look at how many different cleaning products are lemon-scented." The only downside is that lemons are highly acidic (that's what kills the bacteria, after all), so if you're prone to irritation, especially after shaving, be careful. Additionally, be mindful of sun exposure before making lemons your main squeeze. "Lemon juice makes your skin photosensitive, meaning the sun changes something about the juice on your skin and makes it a toxic irritant," says Marmur. Basically, you'll get welts if you put lemon on your skin and then spend too much time in the sun. (No, thanks.)
As for smearing other kinds of fruits on your armpits? Not a great idea. Other citrus sources contain higher levels of sugar and can therefore be sticky; and mangos and limes are known to be photoallergic triggers, according to Marmur.
Moral of the story: If you're in a pinch, like heading to a big meeting when you realize you forgot to put deodorant on, you can neutralize the odor and sweat with lemon juice. And if you're eating mangos or drinking margaritas on the beach (we're jealous), be sure to immediately wash off any juice that winds up on your skin.