PIC: Sara Rue Wears First Bikini After Losing 50 Pounds

She shed 50 pounds in seven months and ran a half marathon last October, but there's one challenge Sara Rue avoided for 33 years.

"I've never worn a bikini in my life!" she tells the new issue of Us Weekly (on stands now). "Not even as a kid. Literally, never."

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That all changed when Rue -- who has been a spokeswoman for Jenny Craig since December 2009 -- slipped into a sexy two-piece for an upcoming ad campaign.

"I looked at the images and said, 'Wow, that looks good. I really like my body,'" star of ABC Family's My Future Boyfriend says.

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The 5'8" actress -- who used to be size 14 and is now a size 4-6 -- credits her lean figure to a 1,200-calorie-a-day diet of Jenny Craig's home-delivered portion-controlled meals. "It worked when everything else failed," Rue tells Us.

To prep for her bikini shoot, Rue -- who runs four to five miles a week -- amped up her workout with hourlong interval training on the treadmill, walking lunches and 100 crunches daily, plus twice-weekly sessions with a trainer.

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"I want someone to have a freaking pool party and invite me," a newly confident Rue tells Us. "Because I can't tell you how many I've turned down!"