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Acne

Acne is a skin condition that affects the hair follicles and the sebaceous glands in the skin, which secrete an oily substance called sebum. Acne is most common on the face, arms, back and chest.

The onset of acne is usually around puberty, but in a minority of cases it may also start in adulthood. About 80% of people will have some degree of acne between the ages of 11 and 30.

In puberty, acne occurs because of changes to hormone levels, which cause the sebaceous glands to produce increased amounts of sebum. Together with dead skin cells, the sebum blocks the hair follicles, which enables the formation of ‘spots’ ranging from blackheads to painful red nodules.

As with the other physical changes that happen during puberty, acne usually corrects itself over time. It most cases it should get better without treatment. However, in some people this may take many years and can potentially cause permanent scarring, so a variety of treatments are available.