What is alopecia, the auto-immune condition American actress Jada Pinkett Smith suffers from?
The US Department of Health and Human Services describes alopecia areata as a condition that arises when the body's immune system attacks hair follicles resulting in hair loss.
The reasons can be genetic or environmental.
There are three types of alopecia. The first is patchy, the most common, in which hair loss occours in one or more 'coin-sized' patches of the scalp or other parts of body.
The second, Totalis, causes people to lose all or nearly all hair on their scalp. And the third, Universalis, is the most rare which results in complete or nearly complete loss of hair on the scalp, face and the rest of the body.
Alopecia is a common condition which over a million Indians reportedly suffer from.
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