With record sales of more than 7 million in the United States and six albums certified platinum, Missy Elliott is one of the most successful female rappers of all time. The last few years, however, have been a challenge for the 39-year-old, as she recently revealed she's been battling a serious autoimmune disease with the unfortunate name of Graves. 

Directly impacting the thyroid, symptoms of Graves can appear suddenly and include hyperactivity, insomnia, muscle weakness and bulging eyes. Elliott was first diagnosed in 2008 after almost crashing her vehicle. 

“I was (driving and) trying to put my foot on the brake, but my leg was jumping,” she told People magazine. “I couldn’t keep the brake down and almost crashed… I couldn’t write because my nervous system was so bad — I couldn’t even use a pen.”

Upon suffering further symptoms, including hair loss and mood swings, Elliott tried radiation therapy, which ultimately helped her cope with the incurable condition. 

“I’m 30 pounds lighter because I’ve been exercising,” she says. “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.”

Other notable cases of Graves include Presidents John Adams and George H.W. Bush (as well as, coincidentally, his wife Barbara) and British comedian Marty Feldman.

More information on the condition can be found by visiting the National Graves' Disease Foundation.