Q What is skin’s acid mantle? —Claire C.
A: You may have heard this term used by skincare experts or seen it on product packaging, since the skin barrier is a hot topic right now. “The acid mantle is a thin film on the surface of our skin that acts as a barricade to bacteria and other viral substances,” says Sandra Lee, M.D., a dermatologist in Upland, CA, and founder of SLMD Skincare. “It’s composed of sweat, natural oils and dead skin cells.” The acid mantle’s slight acidity helps your skin maintain a healthy microbiome, or balance of bacteria, but harsh cleansers and exfoliants can disrupt it. When this happens, it “can lead to certain conditions such as eczema, dermatitis, rosacea and acne,” says Marie Hayag, M.D., a dermatologist in…