Missy Elliott
This rapper's 30 pound weight loss a few years ago wasn't for the sake of vanity, it was to help keep her alive. Missy revealed to People last year that she has been fighting Graves disease since 2008. The autoimmune disorder, which ravages the nervous system and thyroid, and has no cure, caused her to dramatically change her lifestyle and focus on her health. Thankfully, doctor's caught Missy's disease early and said she will be able to live a life close to normal, provided she takes care of herself.