American Idol winner Ruben Studdard will be competing in a different reality show this fall: The Biggest Loser.

The 35-year-old singer, who won season 2 of American Idol in 2003, was announced on Monday to be the first celebrity contestant on The Biggest Loser, which is entering its fifteenth season. Studdard has battled with his weight for years, fluctuating dramatically over the past decade. In 2006, he slimmed down after participating in a healthy eating program for Duke University.

"On both sides of my family, I have a history of diabetes and high blood pressure and things of that nature," he said on The Today Show show in 2006. "I just wanted to basically combat those issues at an early age. They've never been an issue for me, but I wanted to do it while I was still young and felt like working out and looking great."

Studdard gained a lot of the weight back after his divorce from wife Surata Zuri McCants in 2011. He told talk show host Wendy Williams in 2012 that he gained much of the weight due to "stress-eating," though he said he was still trying to get healthy.

"It took me to be in my thirties for it to become somewhat of a mission for me, because I grew up in the South," he told The Huffington Post in last year. "So we used to eat everything. And still to this day I have a problem with sweets, which is something that I hope I can get control over in the near future. But everyone has different obstacles that they have to conquer and I'm looking forward to having the opportunity to conquer mine."

The next step in Studdard's weight loss journey will begin Tuesday, Oct. 8 when The Biggest Loser premieres its fifteenth season on NBC.

Watch Studdard's winning moment on American Idol:

Tags: Ruben Studdard American Idol the biggest loser