From glycolic to salicylic, exfoliating acids have quickly become a mainstay in our beauty routines. But lactic acid seems to be the lesser known of the bunch, despite being a dermatologist’s favorite ...

Lactic acid is an over-the-counter chemical exfoliant that comes from the fermentation of lactose — a carbohydrate found in milk. It's a popular ingredient in numerous skin care products nowadays. But ...