blackheads are one of three types of acne. acne is caused by excessive oil production in the sebaceous glands. the secreations are called sebum and this oil drains into hair follicles. the sebum typically hardens and when it does close to the surface of tthe skin, it forms a plug known as a blackhead. the color of the blackhead is not caused by dirt, but by excess skin pigment, debris and skin particles. keep skin whistle clean and exfoliate regularly.