Word! Sebum

Sebum

Say: see-bum

You can't see it, but it's there. Sebum is your skin's natural oil, and it keeps your skin soft and makes it a bit waterproof. Ever get wrinkly fingers in the tub? Although your fingers may look shriveled like raisins, they aren't really shriveled – they're actually waterlogged because the sebum has been washed away.