Though she has kept it quiet for years, the 'Work It' singer has disclosed that she was diagnosed with the thyroid disease in 2008, after experiencing a frightening loss of muscle control, and has been undergoing treatment since.
"I was [driving and] trying to put my foot on the brake, but my leg was jumping. I couldn't keep the brake down and almost crashed," the Virginia rapper-producer reportedly told People Magazine. "I couldn't write because my nervous system was so bad -- I couldn't even use a pen."
After suffering several other debilitating hyperthyroid symptoms, including mood swings and hair loss, Missy revealed that she turned to radiation treatment, a solution that greatly improved her condition, but cannot cure her of the disease.
"I'm 30 pounds (13.6 kilograms) lighter because I've been exercising," Missy continued. "My thyroid is functioning, so I haven't had to take medication in about nine months. (But) you live with it for the rest of your life."
While Graves' disease is rarely life-threatening, it is not known what causes the disorder, which is five to 10 times more common for women, affecting almost 2 percent of the female population.
On the comeback since her diagnosis, Missy, who turns 40 on July 1, has also announced that she is working on new music with longtime collaborator Timbaland, and will be featured on the June 29 season premiere of VH1's 'Behind the Music,' where she will reportedly further discuss her condition, as well as the sexual abuse she suffered as a child.
*UPDATE: Missy Elliott released this statement to the BoomBox regarding her Graves' Disease diagnosis: "There have been some inaccuracies reported in regards to my diagnosis with Grave's Disease, so I wanted to clear things up. I was diagnosed with Graves' Disease about three years ago but it really hasn't slowed me down at all. I rocked my performance on VH1 Hip Hop Honors' tribute to Timbaland last year. I've written and produced a bunch of Grammy-nominated, #1 hits for artists like Keyshia Cole, Monica and Jasmine Sullivan. I toured the UK, Europe, Asia, Africa and Australia. And on top of all that, I'm working on my new album. I feel great. Under my doctor's supervision, I've been off medication for about a year and I'm completely managing the condition through diet and exercise."