Valerie Bertinelli: Fifty-one and never felt better

You could say that Valerie Bertinelli is aging like a fine wine - with every year she's getting better.

"I've been around so long I can't lie about it," she tells Prevention magazine. "It's an old cliché, but you really do get better as you age. I wish I had the body and the face of that 20-year-old. I'm so glad I don't have her brain."

The "Hot In Cleveland" star is still looking as hot as she did the day she shed 40 pounds and showed off her toned bikini beach bod on the cover of People magazine in 2009.

So how does she do it?

The Jenny Craig spokesperson, who appears on the cover of Prevention magazine's September issue, has been maintaining her weight with portion control and a personal trainer, but admits that you need to splurge once in a while so you don't completely fall off the wagon.

"If I know that I'm going to go out to dinner, I have a light, light breakfast and a light, light lunch, so I can indulge," she adds. "It's more about portions. If I start restricting myself with any food, I'm going to obsess about it. Eventually I'll indulge, and I won't stop."

Bertinelli is also doing a lot of laughing and burning a lot of calories on the set of the Emmy-nominated TV Land show, "Hot in Cleveland" alongside the legendary Betty White.

She is also in a happy and healthy relationship with her second husband, Tom Vitale, whom she has dated for six years before they wed.

"The relationship is the same, but it feels different," she explained. "Making a commitment with our preacher and all our family there just means more. Something digs down deeper into your heart."

But her health and her heart weren't always in tip-top shape, however.

Previously married to musician Eddie Van Halen (they got married when she was just 20 years old), Bertinelli has come a long way to find true happiness. While she's admitted to cocaine use and infidelity while being married to Van Halen, she said she recognizes that was a different period in her life, one that she has learned from.

"Why do women cheat? I don't know. It's a flaw in character. I had that flaw, and all it does is make you feel like crap," she admitted. "I never, ever want to feel that feeling again. It destroyed the trust between me and my first husband."

Let's face it, no marriage is perfect. It takes hard work. But is marriage the second time around any easier?

"We have the old ghosts of our previous marriages that we have to work through," Bertinelli said. "Certain words might trigger what he's heard in the past."

But if it's anything like maintaining a healthy lifestyle, the resilient Bertinelli can keep her calories on track and keep her ghosts of past in check!

The September issue of Prevention magazine is on newsstands now.