Project Activate: Mindfulness and Acceptance Based Behavioral Treatment for Weight Loss

Mindfulness and Acceptance based Behavioral Therapies (MABTs) are among the most promising behavioral approaches for obesity, with two recent large trials showing that they achieve better initial weight loss and/or better weight loss maintenance than does gold standard behavioral weight loss treatment (BT). However, results vary, potentially due to inconsistencies in how MABT components are utilized and emphasized. Optimizing MABTs using a typical approach, i.e., successive randomized controlled trials of various MABT packages, is slow and difficult. Multiphase Optimization Strategy (MOST) has been developed as a better method of optimizing treatment. Consistent with Phase I of MOST, we derived three MABT components from the theoretical literature. Evaluation of MABT components through a factorial design (MOST Phase II) will allow us to determine the independent and interacting efficacies of each MABT component, in addition to the identification of subsets of individuals most or least responsive to each component. Whereas mediational analyses have been inconclusive, the use of a factorial design will allow for a critical test of the main and interaction effects of individual MABT treatment components. The current study will use a full factorial design to identify the independent and combined effects of three core MABT components (Awareness, Acceptance, and Values Clarity) as additions to remotely delivered weight loss counseling. Moderators of treatment outcome (disinhibited eating, food cue susceptibility, emotional eating, delay discounting, and inhibitory control), and mediator/process variables implicated in MABTs (mindful eating, acceptance of food cues, mindfulness, body responsiveness, autonomous motivation, values clarity, hunger/satiety perceptions, and motivation and pleasure resulting from social functioning) will be assessed as well.