As I explained thoroughly under cleansing, exfoliation is essential to remove dead skin cells. We shed dead skin cells constantly, but we need to stimulate this process as we age and for those that have acne in particular. When dead skin cells accumulate, they act like a blanket on our skin, thus preventing our natural oils from coming out and preventing anything beneficial that we apply from going into the skin. When our natural oils cannot come out to the surface, we develop black heads, whiteheads, and pimples. It is crucial to good skin hygiene to help this natural exfoliation process along. There are many different types of exfoliation ingredients we can use such as: enzymes, scrubs, acids and derivatives of Vitamin A.