When we have overactive sebaceous glands the skin produces too much oil which we call sebum. too much sebum makes the face appear oily and shiny. This sebum also clogs the pores and as a result you get bumps and even acne. If we do not treat the over activity the oils can weaken the skin and make it more vulnerable to harmful bacteria. the oil can trap environmental pollutants, debris, & dirt which can cause blackheads and acne. Since the skins defense is compromised it makes it difficult to reject the bacteria. disregarding the build up of oil is going to cause congestion in the skin, and acne will develop when the glands mix with the dead skin cells and the dirt to suffocate and clog the pores. Here is a list of some great acne products to try.