https://apnews.com/625f0635f891989677ac9cd2fbe54e7b > A disease that causes hair loss is at the center of the most talked-about moment at Sunday’s Oscars ceremony. Actress Jada Pinkett Smith disclosed four years ago that she has alopecia and it’s the reason she has shaved her head or worn turbans in public. > It’s unclear if comedian Chris Rock knew that when he joked about her baldness during Sunday night’s ceremony, but Smith grimaced and her husband, actor Will Smith, strode to the stage, smacked Rock in the face and profanely told him not to talk about his wife.