Modeling interactions between brain function, diet adherence behaviors, and weight loss success

Summary Introduction: Obesity is linked to altered activation in reward and control brain cir-cuitry; however, the associated brain activity related to successful or unsuccessful weight loss (WL) is unclear. Methods: Adults with obesity (N = 75) completed a baseline functional magnetic res-onance imaging (fMRI) scan before entering a WL intervention (ie,3-month diet and physical activity [PA] program). We conducted an exploratory analysis to identify the contributions of baseline brain activation, adherence behavior patterns, and the asso-ciated connections to WL at the conclusion of a 3-month WL intervention. Food cue-reactivity brain regions were functionally identified using fMRI to index brain activation to food vs nonfood cues. Food consumption, PA, and class attendance were collected weekly during the 3-month intervention. Results: The left middle frontal gyrus (L-MFG, BA 46) and right middle frontal gyrus (R-MFG; BA 9) were positively activated when viewing food compared with nonfood images. Structural equation modeling with bootstrapping was used to investigate a hypothesized path model and revealed the following significant paths: (1) attendance to 3-month WL, (2) R-MFG to attendance, and (3) indirect effects of R-MFG through attendance on WL. Conclusion: Findings suggest that brain activation to appetitive food cues predicts future WL through mediating session attendance, diet, and PA. This study contrib-utes to the growing evidence of the importance of food cue reactivity and self-regulation brain regions and their impact on WL outcomes