Kelly Osbourne

After struggling with her weight her entire life, Kelly Osbourne says she's finally found the secret to shedding pounds and keeping them off.

The daughter of Sharon and Ozzy Osbourne, who's now a fashion correspondent for E!, has said that criticism of her appearance in the media is partially what led to her drug use and landed her in rehab three times. And even after she got clean, Osbourne still struggled with addiction of a different kind — to food.

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But when she was cast on Dancing with the Stars in 2009, Osbourne says she was forced to begin a new diet and exercise routine. She eventually lost 20 pounds during her time on the show, and lost another 30 after the show with a personal trainer.

"[Working out] is something I really enjoy doing," Osbourne tells In Touch. "I never thought I'd be that kind of girl."

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Osbourne says she recruits friends to work out with her, and varies her routine so it doesn't get boring. She incorporates cardio, circuit training, yoga and Pilates, according to In Touch.

Though she admits "indulging" in a former staple, pizza, once a week now, Osbourne says her overall eating habits are much healthier. "For breakfast, I will eat either cereal or a little omelet thingy made with egg whites, mushrooms and spinach," she tells In Touch. "Lunch is usually a salad or a turkey burger. And then for dinner, I'll have brown rice with vegetables and some kind of meat."