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 ...
Medically reviewed by William Truswell, MD Key Takeaways Different types of pimples can form on your skin, such as papules, pustules, and cysts. Over-the-counter treatments with ingredients like ...