On social media, an interesting option for reducing body odor is gaining popularity. It involves applying toner on your armpits to decrease B.O. But does it work? According to dermatologists and beauty experts, toners can effectively lower the armpit’s pH levels, making the environment less hospitable to bacteria responsible for odor. Because the underarm area is delicate, experts recommend using a gentle formula that contains soothing and moisturizing ingredients like rose water.