Eye Makeup
Worst-case scenario: Conjunctivitis
Why? The damp mucous membrane of your eye is like a VIP entrance for bacteria. It just doesn’t have the same layers of protection that the skin does, making transmission easy for infections like pinkeye.
Razors
Worst-case scenario: Staph or blood-borne viruses (like HIV)
Why? Razors can draw blood or fluids, which leave bacteria on the blade after rinsing, says Deborah Sarnoff, M.D., a derm in NYC. Via nicks or abrasions, you’re vulnerable to a staph infection, hepatitis, and even — although highly unlikely — HIV.
Makeup Brushes
Worst-case scenario: A skin infection
Why? Bacteria love burrowing themselves in makeup brushes. They’re often damp from products (like foundation) or the environment (like humid bathrooms). Borrow someone’s brush and you’re dusting their germs onto your face and contaminating your product.
Anything in a Jar
Worst-case scenario: A skin infection
Why? Every time someone dips her finger into a jar of face cream or foundation, surface bacteria hitchhike into the formula and incubate (bacteria love a dark, damp environment). Dip into a bad batch and you could transfer that funk to your face. To minimize the odds, stick to your own stuff and always apply it with clean hands.
Face-cleansing brush
Worst-case scenario: A skin infection
Why? After cleansing, those bristles become packed with dead skin cells and sebum, which bacteria feed on. Buffing someone else’s germs into your pores? That’s an invitation for trouble — even infection. Go ahead and share a unit, but use your own brush head (clean it after each use) and replace it after three months.
Lip color
Worst-case scenario: Colds and cold sores
Why? The mouth (which itself is a bacteria bonanza) doesn’t have the same outermost epidermal layer of skin, says NYC dermatologist Julie Karen, M.D., leaving it susceptible to infections like herpes simplex virus type 1 (check that cold sore) and, more commonly, colds.
This article was originally published as “Hey, Can I Borrow That?” in the February 2015 issue of Cosmopolitan. Click here to get the issue in the iTunes store!
