Brain function predictors and outcome of weight loss and weight loss maintenance

Abstract

Obesity rates are associated with public health consequences and rising health care costs. Weight loss interventions, while effective, do not work for everyone, and weight regain is a significant problem. Eating behavior is influenced by a convergence of processes in the brain, including homeostatic factors and motivational processing that are important contributors to overeating. Initial neuroimaging studies have identified brain regions that respond differently to visual food cues in obese and healthy weight individuals that are positively correlated with reports of hunger in obese participants. While these findings provide mechanisms of overeating, many important questions remain. It is not known whether brain activation patterns change after weight loss, or if they change differentially based on amount of weight lost. Also, little is understood regarding biological processes that contribute to long-term weight maintenance. This study will use neuroimaging in participants while viewing food and non-food images. Functional Magnetic Resonance Imaging will take place before and after completion of a twelve-week weight loss intervention. Obese participants will be followed though a 6-month maintenance period. The study will address three aims: 1. Characterize brain activation underlying food motivation and impulsive behaviors in obese individuals. 2. Identify brain activation changes and predictors of weight loss. 3. Identify brain activation predictors of weight loss maintenance. Findings from this study will have implications for understanding mechanisms of obesity, weight loss, and weight maintenance. Results will be significant to public health and could lead to a better understanding of how differences in brain activation relate to obesity.

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

“…The present investigation is an analysis from the first 3 months (12 weeks) of a 9‐month study. A detailed description of the materials and methods for this study can be found in Szabo‐Reed et al This study consisted of a 12‐week diet followed by a 6‐month maintenance period. Functional magnetic resonance imaging (fMRI) scans were completed on participants with obesity (BMI 30 to 45 kg/m 2 ) with a visual food cue reactivity fMRI paradigm in a baseline session before participants entered the weight management program.…”

“…Baseline demographics and sample characteristics are included in Table . All inclusion and exclusion criteria have been previously detailed elsewhere . Briefly, participants were included in the study if they met the following inclusion criteria: (1) age 21 to 55 years, (2) BMI of ≥30.0 to 45.0 kg/m 2 , and (3) clearance for participation from their primary care physician.…”

“…Participants viewed pictures of food, animals, and blurred low‐level baseline images after fasting at least 4 hours and after consuming a standardized meal . Food and animal images were obtained from professional stock photography and matched on brightness, resolution, and size.…”

“…All images were presented one time only to each subject. Validation procedures for these images are outlined in a previous publication …”

Voxel‐based morphometry reveals brain gray matter volume changes in successful dieters

“…The details of this investigation have been previously published ; therefore, a brief description of the methods has been provided.…”