Cause of Alopecia Areata
Although alopecia areata is thought to be caused by an autoimmune disease, research scientists are still unsure why the immune system attacks the hair follicles and stunts hair production. When white blood cells attack the rapidly growing cells in the hair follicles that make the hair, the follicles become small, and hair production is drastically slowed. This process may be linked to certain genes.
Alopecia areata is considered to be an autoimmune disease, in which the immune system (which protects the body from foreign invaders such as viruses and bacteria) mistakenly attacks the hair follicles. This can lead to hair loss on the scalp and elsewhere.
In alopecia areata, white blood cells (which are part of the immune system) attack the rapidly growing cells in the hair follicles that make the hair. The affected hair follicles become small, which drastically slows down hair production. Fortunately, the stem cells that continually supply the follicle with new cells do not seem to be targeted, which means that the hair follicles always have the potential to grow more hair.
Scientists do not know how alopecia areata causes the hair follicles to slow down hair production. However, they do suspect that a combination of genes may predispose some people to this condition. In those who are genetically predisposed, some type of trigger -- perhaps a virus or something in the person's environment -- brings on the attack against the hair follicles.