Acne is a very common skin condition. According to NHS Choices, about 80 per cent of people aged between 11 and 30 will be affected by acne to some extent. The medical term for acne is acne vulgaris €“ 'vulgaris' meaning 'common.' Acne is most common between the ages of 14 and 17 in girls, and 16 and 19 in boys €“around the time when the hormonal changes of puberty peak.

In general, symptoms tend to improve as the person gets older and usually disappear when they're in their mid-20s. However, for some people, acne remains an issue into adult life €“ about five per cent of women and one per cent of men have acne over the age of 25.

In adults, about 80 per cent of acne cases occur in women. Symptoms are often linked to changes in hormone levels, such as just before a woman's period is due or during the early stages of pregnancy. Women with polycystic ovary syndrome may also suffer from acne.

There is some evidence that suggests acne runs in families. It has been suggested that if both parents suffered from acne then their child is more likely to develop acne at an earlier age and their symptoms may be more severe. Research also suggests that if one or both parents had adult acne, their child is more likely to suffer from adult acne as well.