Keratosis Pilaris | Causes & Risk Factors


Who gets keratosis pilaris?

Keratosis pilaris can occur at any age and affect anyone, but it usually appears during the first 10 years of life. It generally affects women more often than men. It can worsen during pregnancy and after childbirth, or during puberty. Keratosis pilaris may disappear or improve with age.

Many people who have keratosis pilaris have a family history of it. About 40% of adults and 50% to 80% of adolescents have it.

What causes keratosis pilaris?

Keratosis pilaris occurs when the protein (keratin) in dead skin cells plugs hair follicles (tiny duct-like openings) and causes the bumps to form. It is not caused by a fungus, bacteria or a virus. Keratosis pilaris is not contagious. It occurs more often in dry, winter months, and tends to improve in warmer months when humidity is higher.

Written by editorial staff

Reviewed/Updated: 04/14
Created: 10/09