What is acne?

Acne is a very common skin disorder of the pilosebaceous units. The pilosebaceous units consist of sebaceous glands connected to a follicle, or canal, lined with keratinocytes, which are a type of skin cell, and containing a fine hair. The sebaceous glands produce skin oils (sebum). Acne is often inflammatory and is characterized by clogged pores called comedones and pimples, which may or may not contain pus. These lesions are due in part to the excessive production of sebum. Acne is not a serious medical condition, and can usually be kept under control with treatment. Although scarring is common, treatment during and after an outbreak can help.

How common is acne?

Acne is the most common skin condition affecting people worldwide. According to the National Institute of Arthritis and Musculoskeletal and Skin Diseases, 80 percent of all people between the ages of 11 and 30 develop acne.

When is acne most likely to develop?

Acne is most common in teenagers and onset usually occurs in puberty, when androgens, or male sex hormones, increase in both males and females. This increase in androgens causes the sebaceous glands to become bigger and more active. Although usually associated with teenagers, acne can affect people of all ages, even infants. Onset may occur in adulthood or breakouts that began during adolescence may continue into adulthood. Acne usually goes away by the age of 30, but this is not always the case. It is not uncommon for people in their 20s or 30s to have the condition, and it may continue to affect people in their 40s and 50s. During adolescence, acne is more common in males than in females. In adulthood, it affects women more often than men.