What Causes Acne. Which builds up and becomes blocked creating comedones (blackheads and whiteheads).The acne bacteria feeds, grows and multiplies in the oil from the blocked pores.

Resulting in papules and pustules(pimples and zits).The inflamed pores(hair follicle) and the oil gland causes the skin around it to also become inflamed creating nodules(lumps and cysts). The inflammation also harms collagen cells.

If it produces less collagen this create what is called thinning of the skin or depressed scaring. It is a combined effect of the acne bacteria, hormones(male - testosterone and dihydrotestosterone) and a overactive oil gland blocking pores and creating inflammation.

When the pores are blocked at the surface it encourages more oil production creating bacteria and inflammation which lead to pimples or zits.Hair spray, oil based cosmetics, oils and greases can contribute to blocking the hair follicle at the surface.