Male pattern baldness, or androgenetic alopecia, is related to male hormones and family genetics. Hair loss in men usually begins with a receding hairline and thinning hair on the crown.
It is caused by a very sensitive reaction to DHT (dihydrotestosterone), which is a type of testosterone. The response causes hair follicles to shrink and as a result they lose the ability to grow new hair. In addition, this also shortens the lifespan of hair follicles so you lose hair more quickly and frequently. Male baldness is a combination of losing hair more quickly, with a slower growth and replacement rate.
Hair loss or hair thinning can also be caused by stress, poor diet, hormone imbalance, illness or your body going into shock. Certain diseases and intensive medical treatment such as chemotherapy are also likely to result in hair loss, but it is best to consult your doctor if you go bald at an alarmingly fast rate, especially if you have no family history of male hair loss.
