Androgenetic alopecia is the type of hair loss commonly known as “male pattern baldness”. In men, the characteristic pattern of hair loss is along the front and sides of the head, while in women it involves central thinning. This type of hair loss in both men and women is usually genetic, but may be caused by hormone irregularities in women (hyperandrogenism –excess male hormones). Minoxidil (Rogaine) is the most commonly recommended medical treatment if the hair loss is not advanced and not due to some other underlying condition. The response rate is dependent on severity of hair loss and may cause adverse effects.
Clinicians have been well aware of the deleterious effects of ultraviolet radiation (UVR) from the sun, like cancer and skin disorders, on the balding scalp, but for the most part had not considered the effect on the hair loss itself. An article published in Dermatology (2003;207(4):343-348) discusses some previous findings related to the effect of sun on the exposed scalp. The author states that UVR can increase overall hair shedding, and can elevate oxidative damage with resultant inflammation in the hair follicle which can be mediated by bacteria in the ducts and from increased production of inflammatory chemicals from skin cells.
The study concludes that androgenetic alopecia can be aggravated by sun exposure due to the effect of UVR on physiologic and biochemical processes in and around the hair follicle. He states that the scalp should be protected from the sun to limit both hair loss and prevent skin cancer and other dermatologic disorders.
Posted by Kristopher Foster on May 2, 2006 10:27 AM
