| Excessive sebum production secondary to sebaceous gland hyperplasia is the first abnormality to occur. |
| Testosterone causes excessive sebum to be secreted from the skin's sebaceous glands. |
| The oily sebum rises up through the hair follicle, providing lubrication for your skin and hair. |
| These sebaceous glands normally produce sebum, a substance which moisturizes the skin. |
| Sebaceous glands secrete sebum, and in skin they are thought to have bacteriostatic, emollient, and barrier functions in humans. |
| The resulting build up of sebum behind the blockage helps produce blackheads and whiteheads. |
