BET YOUR LIFE

"[Will] said I had to take care of my health,” says the host of Power 106's "Big Boy's Neighborhood,” a successful morning show. At the time, Alexander weighed 511 pounds and had heard all the warnings before. "He wasn't saying anything new,” Alexander remembers. "It was really out of concern.”

So Smith and Big Boy came up with a wager: For every pund Alexander lost, Smith would donate $1,000 to charity. In six months, Alexander lost 111 pounds through diet and exercise, leading Smith to give to various charities, including Children's Hospital in LA. But, like millions of dieters in the U.S., Alexander gained most of it back before long. When his legs were swollen for two days after returning from a business trip, Alexander tried again for fear, he recalls, that "I was going to die.”