Inherited hair loss
About half the population have some hair loss by about 50 years of age. Men may start losing hair between the ages of 15 and 25, and women are more likely to start losing hair between the ages of 25 and 30, or in some cases, after menopause.1
With inherited hair loss (androgenetic alopecia), men tend to lose hair on the front hairline and temples and on top of the head. Eventually, they may go completely bald.
Women generally lose less hair than men, but they have a similar pattern of hair loss. Women may have slight, moderate, or even severe hair loss, but they don't usually lose all their hair.
For both men and women, inherited hair loss must be treated early for hair to regrow.
Other causes of hair loss
Alopecia areata is hair loss caused when the immune system attacks hair follicles , where hair growth begins. It usually starts with one or more small, round, smooth bald patches on the scalp, and can progress to total scalp hair loss or complete body hair loss. It often begins in childhood. The hair usually grows back within 1 year. But hair loss in alopecia areata can come and go-the hair often will grow back over several months in one area but will fall out in another area.
With hair loss caused by stress, disease, medicines or medical treatments, clumps of hair may fall out. But after the cause is stopped, the hair usually grows back, although sometimes treatment may be needed.