There’s no shortage of weight-loss plans out there. But how do you know which one’s right for you? A new study from the University of Pennsylvania’s Perelman School of Medicine suggests it may come down to the personality traits that make you…well, you.

A team of researchers led by X. Shirley Chen, M.D., re-analyzed data from a 2019 study that sought to identify the best way to motivate overweight and/or obese adults to become more physically active. The 602 participants, all of whom committed to walking more and wearing a step-counter to chart their progress, were randomized into three groups defined by their style of behavioral intervention:

Competitive: participants’ step counts were posted on a leaderboard.
Collaborative: participants were assigned teams, and their step counts were combined.
Supportive: participants sent step reports to a designated friend or family member.

After 24 weeks with the intervention and 12 without, the competitive group’s step total was significantly higher than the others. But when Dr. Chen reviewed the data, she observed wide variations among individuals and theorized that this might be due to their different personality traits. 

Re-evaluating the 2019 data through the lens of “personality,” Dr. Chen found that competitive weight loss plans were actually not the best plan for extroverted and motivated participants. Their step counts increased at first, only to drop off once the leaderboards were gone. By contrast, all weight loss plans worked for those who were less social and less active, while none worked for the less active and at-risk group.