Randy Jackson. Photo: EPA/NINA PROMMER

Randy Jackson is opening up about his tremendous weight loss.

The renowned "American Idol" judge revealed to People exactly what it took to lose 114-pounds. Jackson, now 63, had gastric bypass surgery in 2003.

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“For a long time you see me on TV and people have noticed me in the past and I was struggling with my weight, then I finally got it off by using some pretty drastic measures,” he shared. I think it was season 2 on 'Idol'. You come in and they go ‘Yeah dawg, you’re telling me I’m terrible but you’re fat!’ And I would go, ‘I am. I have mirrors in my house. I know!’"

"So I think that finally, it was that and also I had an emergency room visit that I thought I was really sick and had a cold or something," Jackson continued, adding he was diagnosed with type 2 diabetes. "Managing type 2 diabetes also runs hand in hand with managing your weight."

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Jackson's weight loss journey included weight loss surgery, fitness experts, nutritionists and mental health experts.

“You have to change the way you think about food,” he concluded. “You have to almost have a complete divorce break up… and start back bit by bit and find out the things that work with your body and you also find out the allergies and really pay attention to how you feel.”