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Sunscreens and hair photoprotection
1Department of Dermatology, Wake Forest University School of Medicine, Winston-Salem, NC 27262, USA. zdraelos@northstate.net
Abstract:
Photoprotection as it pertains to hair is not a common topic addressed by the dermatologist. Hair is nonliving and requires no protection from ultraviolet (UV) radiation because carcinogenesis of the hair shaft itself is not possible. If hair proteins are altered by sun exposure, damaged hair can be removed and replaced by new growth. Thus, at first glance, the whole issue of photoprotection for the hair might seem irrelevant; however, patients frequently consult the dermatologist for advice on hair growth and appearance problems. Hair photoprotection is an important part of maintaining the cosmetic value of the hair shaft. This article focuses on the chemical effects of UV radiation on the hair shaft, hair photoaging, intrinsic hair UV photoprotective mechanisms, and the use of hair sunscreens. The whole science of hair and photoprotection is currently in its infancy and an area of focused research within the hair care product and salon industries.
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