Alopecia can affect both men and women and it is not uncommon to see children affected with this disorder. Approximately 2% of the general population worldwide suffers from alopecia areata.
'''Understanding alopecia areata:'''
The hair is made up of a protein called keratin which is also the main constituent of nails. A specialised structure inside the skin called ‘Papilla' produces the hair as shown in the figure. The papilla is surrounded by a sac-like structure called the ‘Hair follicle' which also surrounds rest of the hair root within the skin. The part of the hair outside the skin surface is called as shaft. [http://www.alopeciaareata.us/what.htm Source]
[[image: alopecia1.jpeg|500 px|center|thumb]]