It's caused by increased sensitivity to male sex hormones (androgens) in certain parts of the scalp, and is passed on from generation to generation.
In the past, baldness was often seen as something unfortunate or undesirable. However, this attitude has changed over the years and nowadays a clean-shaven head is usually considered both fashionable and attractive.
Some men have areas on the scalp that are very sensitive to the male sex hormones that circulate in men's blood.
The hormones make the hair follicles – from which hair grows – shrink. Eventually, they become so small that they cannot replace lost hairs. The follicles are still alive, but are no longer able to perform their task.
The condition usually starts in men aged 20 to 30 and follows a typical pattern.
First, a receding hairline develops, and gradually the hair on top of the head also begins to thin.
Eventually, the two balding areas meet to form a typical U-shape around the back and sides of the head. The hair that remains is often finer and does not grow as quickly as it used to.
Male hair loss is genetically determined (passed on from parents). Although a doctor can offer medical treatment to improve the condition, this may have side effects.
You need to decide how you feel about hair loss. Male hair loss affects a large part of the male population and people react very differently to it.
It is important to try to accept hair loss for what it is – something natural.
Rather than trying to camouflage bald spots with remaining hair or a wig, it is probably a better idea to leave your hair as it is, or shave it off completely.
If, however, you decide to try to regain your hair, possible medical treatments are discussed below.
Baldness is generally regarded as natural, and not a disease.
So if a person decides they wish to try to get their hair back, they will probably have to pay for the lengthy, expensive procedure themselves.