Millions of people around the world are affected by alopecia areata, an autoimmune disorder that causes hair loss and was thrown into the spotlight after actor Will Smith slapped comedian Chris Rock at the Oscars. The slap stunned millions, drew widespread condemnation and earned Smith a 10-year ban from the ceremony after he apologize. It came after Rock made a pointed joke about Jada Pinkett Smith's hair loss. Advocates said then that increased awareness about the condition could be a small bit of good to come out of the blowup. On Wednesday, Jada Pinkett Smith dedicated an episode of “Red Table Talk” to the disorder, which is fairly common but little discussed,