Jennie Garth Explains How She Got So Skinny

Lookin' good, Jennie Garth!

Though her recently slimmer frame raised eyebrows earlier this summer, newly-divorced Garth confirms she's losing weight the old-fashioned way: Through a careful diet and lots of exercise.

"I'm just taking care of myself: Eating less, exercising more, drinking a lot of coconut water," Garth, 40, told Us Weekly at Thursday's Old Navy Denim Pop-Up Bar event in Los Angeles.

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Garth has admitted that her March split from Peter Facinelli after 11 years of marriage has taken a toll on her body, but says that she's not necessarily reaching for comfort foods all of the time. "I eat a lot of Greek yogurt: Greek yogurt in the morning, salads and proteins the rest of the day and maybe a cupcake if I've been a good girl," explains Garth, who works out with a trainer. "I don't believe in depriving yourself of things you want."

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The mom of three daughters, Garth has begun to start dating again in the wake of her split. "She's happier than ever!" says a friend of Garth, who romanced HGTV star Antonio Ballatore post-split and has recently been on dates with hunky photographer Noah Abrams.

PHOTOS: Jennie's life with her girls

Thursday's Old Navy party provided Garth with an opportunity to show off her slender, sexy new bod to her old pal Luke Perry, with whom she recently reunited to film an Old Navy commercial. "It was weird, it was like no time had passed and we were back on the set again," Garth tells Us of filming the commercial with her former "Beverly Hills, 90210" co-star. In fact, their Old Navy reunion is a sign of things to come.

"We want to work together again because we really love each other and it would be nice to spend time together working," says Garth, who is currently writing a sitcom with Perry, 45. Adds the actor, who played "90210's" Dylan: "t's a good day at work when you're with people you know and that you like."

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