Janet Jackson: How I Got Thin

Janet Jackson Venturelli/WireImage.com; Nutrisystem

It's hard to believe that just six years ago, Janet Jackson weighed 180 pounds.

At 5-foot-4, the "Rhythm Nation" singer had struggled to maintain a healthy weight for most of her career — until she joined the Nutrisystem program in late 2011.

"People can relate to me because I have lived it. I truly understand what it's like to have a problem with weight loss, losing too much weight or gaining more than you desire," Jackson, 45, tells Us Weekly. "It's about keeping it off. We can all lose weight, but learning how to keep it off — maintaining it — is what's difficult. Nutrisystem teaches you how to do that."

Jackson doesn't have a goal weight in mind, though "there was a time in my life where I did live by the scale," she admits.

Part of the reason Jackson decided to represent the Nutrisystem brand is because she still gets to eat her favorite foods. "The snacks are incredible. The cookies, the cakes, the brownies — I love the chips!"

"You don't have to deprive yourself of things that you love, and that's what's so great about Nutrisystem," she explains. "I eat the some of these things and you think to yourself, 'Oh, I shouldn't be having this!' because it's so good!"

The multiplatinum singer also exercises regularly with trainer Tony Martinez in order to achieve faster, more noticeable results.

"Right now I love running, so I've been doing a lot of running," Jackson tells Us. "I can't take someone yelling in my ear bootcamp style. . .He knows he needs to mix it up and make it different every day. He makes sure it's not boring because then I won't want to do it."

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