Kirstie Alley is notorious for her weight loss just as much as she is for her weight gain!

The 66-year-old actress has made headlines through the years for her constant change in weight. It wasn't until she began using the Jenny Craig diet that she was able to lose the pounds and keep them off for good.

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Kirstie has also attributed her positive weight loss results from being on Dancing with the Stars.

"Dancing with the Stars made me alive again," she said. "It's given me a new view on what I want to do with my life."

Watch the video below to see Kirstie's weight transformation through the years!