More than 70% of adults in the United States are overweight and obese. Many weight loss programs and mobile apps use gamification to engage individuals in behaviors to promote weight loss; however, they are often designed using standard economics, which assumes that individuals act rationally and make decisions in line with their long-term goals. Behavioral economics uses insights from psychology to explain how individuals act irrationally but in predictable ways.
We designed a 9-month gamification-based weight loss program leveraging insights from behavioral economics to enhance social incentives. Obese adults formed teams of two and were randomly assigned to a control group or one of two gamification interventions. All participants received a wireless weight scale and used a mobile app on their smartphone to track physical activity. In one intervention arm, teams were entered into the game. In the other intervention arm, teams were entered into the game and data on weight and physical activity was shared with each participant’s primary care physician either through Apple HealthKit integration to Epic or by a mailed letter.
We found that at 24 and 36 weeks, participants in the gamification arms had greater average weight loss than in the control arm, but it was not statistically significant. In subset analyses, we found that participants who lived together lost more weight than those that lived separately, which could help to inform the design of future weight loss programs.