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Male Pattern Baldness Causes

Androgenetic alopecia or male pattern baldness (MPB) is responsible for the vast majority of hair loss in men. While there are many possible reasons people lose hair, including serious diseases, reaction to certain medications, and, in rare cases, extremely stressful events, most hair loss in men can be blamed on heredity.

What male pattern baldness sufferers inherit are hair follicles with a genetic sensitivity to dihydrotestosterone (DHT). Hair follicles sensitive to DHT begin to miniaturize, shortening the lifespan of each hair follicle affected. Eventually, these affected follicles stop producing cosmetically acceptable hair.

Male pattern baldness is generally characterized with the onset of a receding hairline and thinning crown. Hair in these areas including the temples and mid-anterior scalp appear to be the most sensitive to DHT. This pattern eventually progresses into more apparent baldness throughout the entire top of the scalp, leaving only a rim or "horseshoe" pattern of hair remaining in the more advanced stages of MPB. For some men, even this remaining rim of hair can be affected by DHT.

What Is DHT?

Dihydrotestosterone (DHT) is a derivative or by-product of testosterone. Testosterone converts to DHT with the aid of the enzyme 5-alpha-reductase. While the entire genetic process of MPB is not completely understood, scientists do know that DHT shrinks hair follicles, and that when DHT is suppressed, hair follicles continue to thrive.

Hair follicles that are sensitive to DHT must be exposed to the hormone for a prolonged period of time for the affected follicle to complete the miniaturization process. Today, with proper intervention, this process can be slowed or even stopped if caught early enough.

What male pattern baldness sufferers inherit are hair follicles with a genetic sensitivity to dihydrotestosterone (DHT). Dihydrotestosterone (DHT) is a derivative or by-product of testosterone.

Published on March 1, 2010

WebMD Medical Reference from the American Hair Loss Association

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