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Lisa Rinna didn't think twice about posing in Playboy at her age.

"I'm 45 years old. I look good right now. Why not?" she tells Extra. "Why not celebrate the beauty of the female body?"

See photos of stars who are 40 and fabulous.

Rinna says she's happiest in the buff.

"I never feel more comfortable than when I am naked taking pictures," she says. "I don't know what that's about. It's the craziest thing."

Husband Harry Hamlin doesn't mind, either.

"They're awesome," Hamlin said after checking out the photos. "They're amazing. I mean, look at who the subject was!"

Check out pictures of stars working out.

Rinna says she works out "a lot" to maintain her bod.

"Doing Dancing with the Stars changed my body and I never let it go back. I got that body and was like, 'I like this. I'm going to keep it,'" she says. "And I did.So six days a week. I run and walk, dance. I do Pilates...I spin."

See photos of stars dancing.