Hair breakage in normal and weathered hair: focus on the Black patient.

Hair breakage and fragility are a large problem for many patients as well as a treatment challenge to the dermatologist. Understanding the factors that lead to acquired hair shaft fragility and breakage is paramount to recommending appropriate treatment to affected patients. African or Black hair is known to be more affected by breakage with easily observed fragility in vivo. To date there are no known structural or chemical differences in Black hair as compared to Caucasian or Asian hair that explains this observed fragility. This review explores the impact of hair care practices on the development of hair breakage with a focus on patients of color. The examination and recommended ancillary testing for the process are discussed, and advances in the measurement of mechanical fracture of human hair are reviewed.