Missy Elliott performed on Thursday night at the Alexander Wang H&M Collection’s New York launch demonstrating a noticeably slimmer figure.

Elliott, 43, was diagnosed with a rare autoimmune disorder in 2008 known as Graves’ disease. She revealed the thyroid-affecting condition publicly in 2011 and has since made a limited number of concert appearances, admitting to People at the time that, “I couldn’t write because my nervous system was so bad — I couldn’t even use a pen.”

Alexander Wang X HM Launch - Party TheGrio.com
NEW YORK, NY – OCTOBER 16: Musician Missy Elliott performs onstage at the Alexander Wang X H&M Launch on October 16, 2014 in New York City. (Photo by Andrew H. Walker/Getty Images for H&M)

The performance was a surprise for attendees of the fashion show, as Missy Elliott performed her hits “Get Ya Freak On” and “Work It.” In a picture tweeted from Elliott’s account thanking Alexander Wang and H&M after the show, the rapper wears a “You Can’t Workout With Us” hat and Nike sweatshirt.

The weight loss is part of a revised diet and exercise program meant to manage the disease, which has no cure. Elliott has lost almost 70 pounds since beginning the regimen, according to the Daily Mail, although the rapper hasn’t revealed exactly how much weight she lost. In an interview with BET last year, she said, “I’m 30 pounds (13.6 kilograms) lighter because I’ve been exercising.”