When you exercise or otherwise get overheated, your sweat glands produce a watery substance designed to regulate body temperature. But emotional stress triggers different glands—the apocrine glands, which are found mostly in the underarms and groin area—and they secrete a milky fluid. This fight-or-flight-related liquid is made up of water and lipids, so it’s a veritable feast for odor-causing bacteria. Meditation, yoga, and other calming practices may help.
Even guys may want to abandon au naturel underarms. Bacteria thrive in warm, moist environments, and armpit hair can create an ideal swampy habitat. Hair, along with the dirt and oil that accumulate in it, may promote the growth of odor causing bacteria.
4. Apply apple cider vinegar.
Acid, like the kind found in apple cider vinegar or lemon juice, inhibits the growth of bacteria—including the kind that makes your sweat smell gross. Just be cautious, and use it sparingly: While apple cider vinegar and lemon juice may help reduce levels of odor-causing bacteria on the skin, they may cause skin irritation. So if you decide to dab a few drops on your underarms with a cotton ball or add a splash to your bathwater, make sure you have no minor cuts or scrapes. Witch hazel and tea tree oil are also believed to be antimicrobial.