Long‐Term Follow‐up of the Mind Your Health Project: Acceptance‐Based versus Standard Behavioral Treatment for Obesity

Objective In the Mind Your Health Trial, acceptance‐based behavioral treatment (ABT) for obesity outperformed standard behavioral treatment (SBT) at posttreatment. This trial compared effects over 2 years of follow‐up. Methods Participants with overweight or obesity (n = 190) were randomized to 25 sessions of SBT or ABT over 1 year and assessed at months 12 (i.e., posttreatment), 24 (1 year posttreatment), and 36 (2 years posttreatment). Results Weight‐loss differences previously observed at 12 months attenuated by follow‐up, though a large difference was observed in the proportion of treatment completers who maintained 10% weight loss at 36 months (SBT = 17.1% vs. ABT = 31.6%; P = 0.04; intent‐to‐treat: SBT = 14.4% vs. ABT = 25.0%; P = 0.07). The amount of regain between posttreatment and follow‐up did not differ between groups. ABT produced higher quality of life at 24 and 36 months. Autonomous motivation and psychological acceptance of food‐related urges mediated the effect of condition on weight. No moderator effects were identified. Conclusions Overall, results suggest that infusing SBT for weight loss with acceptance‐based strategies enhances weight loss initially, but these effects fade in the years following the withdrawal of treatment. Even so, those receiving ABT were about twice as likely to maintain 10% weight loss at 36 months, and they reported considerably higher quality of life.