Today nearly 90% of men suffer from male pattern baldness, which is called androgenetic alopecia. Most men experience moderate hair loss by the time they reach the age of 50. Men usually start losing hair with a receding hair line or thinning of the crown of the head.
There is no real cause for male pattern baldness; it's just that men are genetically predisposed to male pattern baldness. The effects of hormones on the hair follicles tend to induce male pattern baldness. The hormone testosterone, which increases with puberty, converts to dihydrotestosterone with the help of the enzyme. Dihydrotestosterone acts as a hormone receptor on the hair follicle, and reduces hair production to produce weaker and shorter hair. In some cases, hair growth is stopped completely wherein the stock of hair gets depleted to lead to normal hair loss.