After all these years, Kirstie says she can't believe she's still talking about her weight. "It's humiliating," she says. "The most painful thing for me is that I have all these people that I inspired and then I let them down."

Kirstie says the weight started coming back when she stopped being the Jenny Craig spokeswoman. "When you're a spokesperson for a weight loss company ... somebody weighs you every week. It's pressure but it's good pressure. I do better if I have some pressure on me," she says. "When I didn't have that anymore ... I just said, 'I'm going to cut myself some slack.' Big mistake."

A little slack turned into a lot, and Kirstie says after parting ways with the Jenny Craig company, she didn't weigh herself or work out for a year and a half.