What is male pattern baldness
Male pattern baldness is the common type of hair loss that develops in most men at some stage. The condition is sometimes called androgenetic alopecia. It usually takes 15-25 years to go bald. However, some men go bald in fewer than five years.
What are the Symptoms
- Affected hair follicles on the scalp gradually become smaller than normal.
- As the follicle shrinks, each new hair is thinner than the previous one.
- Before falling out, each new hair grows for much less time than the normal three years or so.
- Eventually, all that remains is a much smaller hair follicle and a thin stump of hair that does not grow out to the skin surface.
What is the cause
Male pattern hair loss is an inherited condition, caused by a genetically determined sensitivity to the effects of dihydrotestosterone, or DHT in some areas of the scalp. DHT is believed to shorten the growth, or anagen, phase of the hair cycle, from a usual duration of 3-6 years to just weeks or months. This causes miniaturisation of the follicles, and producing progressively fewer and finer anagen hairs. The production of DHT is regulated by an enzyme called 5-alpha reductase. Several genes are involved, accounting for differing age of onset, progression, pattern and severity of hair loss in family members. The susceptibility genes are inherited from both mother and father.