Acne is a skin condition that causes pimples or "zits." This includes whiteheads, blackheads, and red, inflamed patches of skin (such as cysts).
Acne occurs when tiny holes on the surface of the skin become clogged. These holes are called pores.
Each pore opens to a follicle. A follicle contains a hair and an oil gland. The oil released by the gland helps remove old skin cells and keeps your skin soft.
When glands produce too much oil, the pores can become blocked. Dirt, bacteria, and cells build up. The blockage is called a plug or comedone.
If the top of the plug is white, it is called a whitehead
If the top of the plug is dark, it is called a blackhead.
If the plug breaks open, swelling and red bumps occur.
Acne that is deep in your skin can cause hard, painful cysts. This is called cystic acne.
Acne is most common in teenagers, but anyone can get acne, even babies. Three out of four teenagers have some acne. Hormonal changes may cause the skin to be more oily.
Acne tends to run in families. It may be triggered by:
Hormonal changes related to puberty, menstrual periods, pregnancy, birth control pills, or stress
Greasy or oily cosmetic and hair products
Certain drugs (such as steroids, testosterone, estrogen, and phenytoin)
High levels of humidity and sweating
Research does not show that chocolate, nuts, and greasy foods cause acne. However, diets high in refined sugars may be related to acne.