Acne > What is acne?

An acne breakout starts in the skin's tiny holes, commonly called pores. It takes about two to three weeks before a blemish shows up on the skin's surface.
Deep within each pore is a sebaceous gland that works to produce sebum, an oil that keeps skin soft and moist. As the skin renews itself, old skin cells die and are shed off. But some people shed skin unevenly and as a result, dead cells mix with sebum and clump together to form a sticky plug. This plug traps oil and bacteria inside the pore — the beginning of a blemish.

Different types
Blackheads and whiteheads, also known as comedones
Comedones are enlarged pores filled with sebum. Blackheads are comedones that have opened onto the skin surface. Whiteheads are comedones that are closed on the surface.

Pimples
These inflamed follicles occur when the P. acnes bacteria in the follicle attracts infection-fighting cells. The follicle may rupture, spilling its contents into the surrounding skin, causing further inflammation.

Nodules and cysts
They represent more severe forms of acne that go deeper into the skin, forming firm, deep bumps and swellings; similar to pimples, they result from increased sebum production, which leads to bacterial growth, irritation and redness.