What's oily, a bit waxy, and secreted from your skin head-to-toe? Though it may not be the most pleasant-sounding skin-care term, sebum is a crucial component of the skin barrier — and when it's ...

Sebum is an oily substance that protect and hydrate the skin’s surface. It mixes with fat molecules, called lipids, to form a protective coating on the skin. The sebaceous glands produce sebum. It ...