Kimberly Calliari paid $300, lost 51 pounds, and won $1,200.
That all happened after she signed up for two challenges on HealthyWage.com, a website that lets dieters bet their own money they’ll meet a weight loss goal. HealthyWage is one of several wagering sites that have been launched in the past few years, including DietBet.com and Stickk.com. GymPact, a smartphone app, pushes people to go to the gym — or get charged for not going. All of the sites have the same premise: Get healthy or risk losing your cash.
‘‘If I didn’t have anything on the line, I don’t think I would have done it,’’ says Calliari, 29, a merchandise buyer for grocery stores in Milwaukee.
The services make money by taking a percentage of the total collected from those who don’t meet their goals. To make sure no one fakes a weight loss, the sites ask users to photograph themselves on a scale or film a video and submit it.
In February 2012, Calliari started two challenges. One was to lose 10 percent of her body weight in six months. She wagered $100. She lost the weight and won $200.
The second was a yearlong challenge to drop her body mass index from obese to healthy. She wagered $300. Her weight dropped from 204 pounds to 153 pounds and her body mass index, a number determined using weight and height, fell to 24 from 33.8. She’ll soon receive a check for $1,000.
‘‘I think it does motivate people,’’ says Susan Adams, assistant professor of nutrition at La Salle University. She says betting $300 might be too much, saying that many people lose the motivation even after paying cash. ‘‘How many people join gyms on Jan. 1? Go back in March and see how many are left,’’ Adams says.
But the thought of losing such a large amount kept Calliari on track. ‘‘If I’m going to spend money on a purse, why can’t I put in $300 for my own health?’’ Calliari says.
If you think money will motivate you to drop the pounds, check out these programs:
Dietbet.comUsers can go on the website and join a public group or create their own private game for family and friends. The wager is set by the person who starts the game. Many public games charge as little as $25. The goal is to lose 4 percent of body weight in four weeks. Those who do share the total amount of money the group collected.
Chief executive Jamie Rosen says about a third of dieters who bet money win money. But about 93 percent of people who join a game lose weight, even if they don’t win cash.
DietBet.com takes as much as 15 percent of the total amount collected before distributing money to winners. Typically, Rosen says, a person who wagers $25 can expect to win $50 to $75 if he sheds 4 percent of body weight.
This app aims to ensure you’re hitting the gym. You make a pact on which days you will go to the gym. You have to wager at least $5 that will be charged if you don’t make it to the gym. Every time you go you have to check in on the GymPact app. GymPact verifies that every gym that is checked in to actually exists. The app uses your smartphone’s global positioning system to make sure you are at your gym for at least 30 minutes. At the end of the week, you get cash rewards for making your goals. The reward money comes from people who didn’t meet their goals.
GymPact takes a 30 percent cut and then distributes it to those that met their goals. GymPact says the average user gets 50 cents to $1 for each time he or she makes it to the gym.
This website lets you select from three challenges. Bet $150 that you’ll lose 10 percent of your body weight in six months, and you could win $300.
If you have a body mass index above 30, which is considered obese by the Centers for Disease Control and Prevention, you can join the 12-month challenge to lower your BMI below 25, which is considered healthy. A free program awards $100 to anyone who completes the BMI Challenge, or you can wager $150 to win $400, or wager $300 to possibly win $1,000.
The third challenge is The Matchup. Users are put in a team of five. It costs $25 a month for three months, and the team that loses the highest percentage of their total weight wins $10,000. But about 150 teams are playing at a time, so the chances of winning any money are slimmer.
There’s no money to win. Users set an amount their credit or debit cards will be charged if they don’t reach a weekly weight-loss goal. The money can be sent to a charity or a friend who you would not want to know about your lack of commitment. You might even try what Stickk calls an anticharity. You can pledge that the money will go to an organization whose mission you don’t support. Stickk collects 29.5 percent of money sent to an anticharity and 19.5 percent of money sent to a charity. You can also use the site without wagering any money and can set other goals, such as quitting smoking.