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Mariah Carey's been making headlines recently for getting her post-baby body back and then some, and now she's sharing her incredible weight loss secrets as the cover girl for May's Shape Magazine.

"I put on around 70 pounds, but if you look at photos of me when I was pregnant, you'd say, 'Wow, she gained 9,000 pounds!,'" Mariah says candidly. "A lot of it was water weight because I pretty much had head-to-toe edema, which is very painful."

Video: Slimmed Down Mariah Carey Debuts New Health PSA

She ended up choosing Jenny Craig to help her lose the weight because she liked "the structure" of the program.

"I used to be able to slim down just by exercising more, but that's changed. Since having the babies, I realize that 90 percent of losing weight is my diet," she says about her current plan. "Today my workout routine is more about getting and staying toned. And for me, that means either taking hour-long walks a few times a week or jumping in the pool three or four days a week to do 45 minutes of aquatic exercises."

Video: Mariah Carey's First Post-Baby Performance

Mariah also gives an update on her husband Nick Cannon's highly publicized health scares.

"It was really frightening, but he's feeling much stronger and is definitely on the right track," she shares. "He's taking better care of himself, eating a diet low in sodium and sugar, and getting more sleep."

And good news for Mariah fans eager for some new music -- the pop star says she hopes to come out with a new album this year!

"I've started writing songs for a new album, which I hope will come out in 2012. Getting back in the studio and making music again -- which I truly love doing -- is the best way to end this crazy year."