By the age of 35, about 60% of males will experience some degree of hair loss. Men who are predisposed to male pattern baldness will typically lose their hair in a defined pattern that starts above both temples (a receding hairline) and then inches back over time to form an “M” shape. However, hair loss can also progress quickly at the crown, gradually advancing until the entire front, top and crown are bald.
Male pattern baldness is caused by the effects of the male hormone dihydrotestosterone (DHT) on genetically susceptible hair follicles located in the front, top and crown of the scalp. DHT causes the hair follicle to shrink in size, both in diameter and length. As a result, the miniaturised follicle produces a small unpigmented vellus hair rather than the usual pigmented normal hair.