In Placing This Weight-Loss Bet, You Lose to Win

— -- When you’re a size 14, the thought of putting on a bridesmaid’s dress can seem daunting, but Christina Maher was up for the challenge.

By the day of her cousin’s wedding, Maher, a 26-year-old who lives in New York City, literally bet she could be down four dress sizes – 40 pounds in six months -- and if she made it, she could win money.

Maher sent $385 each month to HealthyWage, a company that allows users to place bets on its website and phone app that they meet weight loss goals in exchange for cash prizes.

If she achieved her goal, Maher would win $5,000, plus get all her money back, for a grand total of $7,310. But if she didn’t lose the weight, she would be out thousands of dollars.

“I’m re-motivated and ready to go,” Maher said. “I think I really need to get my ass into gear so I can win this bet because I cannot afford not to.”

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HealthyWage says it has already paid out more than $2 million in prize money, yet only one third of participants actually win their bets.

“In our view there’s always a win somewhere,” said Jimmy Fleming, the co-founder of HealthyWage. “I mean the number of people who make a bet and then just fall off the radar are very few. Almost everyone loses some weight. The question is, are you going to accomplish your goal?”

According to some studies, people using money as a motivator are five times more likely to reach their goal weight than if the dieters didn’t have money at stake.

Dave Zinczenko, ABC News’ nutrition and wellness editor and the author of “Eat This, Not That,” and “Eat It to Beat It,” is an expert in diets. He said using money as an incentive to lose weight is becoming more popular but dieters have to be careful.

"One of the big problems with the diet apps is they don’t necessarily teach you how to eat healthfully or exercise efficiently when you don’t have time, space or money," Zinczenko said. "So, you’re not figuring out how to lose weight over the long haul, and the issue is not what you weigh four weeks from now, it’s what you weigh four months from now, or more importantly, four years from now."

At her heaviest, Maher was 295 pounds and her goal was to weigh 194 pounds by the day of her cousin’s wedding.

For Maher, weight has been a lifelong struggle.

“I remember being 6 years old and thinking that I was overweight,” she said. “I got on a scale thinking I was fat, and I’ve never really gotten out of that.”

She said she has never gone off a diet for more than a month.

“[I’ve tried] everything that you can imagine,” Maher said. “It’s funny because I almost feel like I’m such an expert on losing weight… it’s just the actual follow-through that I’ve struggled with over the years.”

As part of her bet against herself through HealthyWage, Maher tracked her weight online by recording every calorie she consumed, and tracked her steps with a FitBit bracelet.

HealthyWage has users take photos of the number on the scale with something that can prove the date, such a copy of today’s newspaper, for regular weigh-ins.

“We’re pretty good at detecting cheaters and making sure that everybody’s actually losing weight and not trying to cheat and get money,” Fleming said. “We have a lot of little tools and strategies to help us make sure that no one is getting away with cheating.”

Although HealthyWage doesn’t advise users on what to eat, they do offer guidance and support to get through the weight-loss process.

“We can’t stop them from doing unhealthy things any more than any other diet program can,” Fleming said. “But our content and all of our motivational tips and emails all revolve around making good healthy decisions and losing weight in a consistent long-term way.”

Two months into her HealthyWage bet, Maher dropped eight pounds, but fell off the wagon a few times.