People who signed up to lose money for failing to meet specific dieting goals lost more weight. In addition, the greatest weight loss success was among people who signed up to have the money they lost donated to a cause they passionately disagreed with.
New findings from the Palo Alto Medical Foundation Research Institute show that people who voluntarily lose money for failing to meet weight-loss goals helps people stay on track for better habits
The study examined 3,857 weight-loss commitment contracts from stickK.com, a site that allows the public to create voluntary personal contracts, with or without a monetary penalty, as a motivation to achieve a specific goal. Anonymity of the participants was protected by having all names removed from the data before the researchers examined it.
The contracts were either penalty or no penalty contracts. In the penalty group, participants had the option of money deducted from a credit card stored on the site either sent to a friend, donated to an organization they agreed with or donated to an organization they disagreed with.
Participants whose contracts included penalties were more likely to meet their weight loss goals and more diligent about reporting their weight each week. (Failure to report your weight every seven days resulted in an automatic penalty that week.)
The participants whose penalties went to a group they disagreed with had the best results. In total, 37.1% of these participants met their final weight goal compared to 24.1% of those whose penalty was set to go to a group or charity they agreed with and 21.1% of those whose penalty went to a friend. The no penalty group had the lowest success rate. Only 5.1% of these participants met their final weight goal.
In addition to being more likely to meet weight loss goals at the end of the contract, those in the penalty group also lost more weight. Weight change per week was -0.33% for those whose penalty went to an organization they disagreed with, -0.28% for those whose penalty went to an organization they agreed with and -0.25% for those whose penalty went to a friend.
Larger financial penalties also correlated slightly with more weight lost. Each $10 per week increase in deposit was associated with a -0.1% weight change per week.
On average, for all contracts there was about a -0.39% weight loss per week. For a 200-pound male with a contract of 16 weeks, this would be about a 10.5-pound weight loss.
The study also found that people who had a person serving as a “referee” or a wireless scale objectively documenting and watching over their progress reported slightly less weight loss.