Title

METABOLIC AND PSYCHOLOGICAL PREDICTORS OF WEIGHT REGAIN AMONG BEHAVIORAL WEIGHT LOSS PARTICIPANTS

Date of Award

2007

Document Type

Dissertation

Degree Name

Doctor of Philosophy (Ph.D.)

Department

Psychology/Clinical

First Advisor

Robert Carels

Abstract

Obesity may soon surpass smoking as the leading contributor to preventable death in the United States. While weight loss treatment outcomes have improved over time, weight loss maintenance following treatment is a significant problem. The present study explored metabolic, psychological and behavioral predictors of weight regain among 40 obese adults 6 months following completion of a 6-month behavioral weight loss program (BWLP). Predictor variables were assessed at pre-treatment, post-treatment, and the 6 month follow-up. Multiple regression analyses revealed statistical trends for higher post-treatment and follow-up resting metabolic rate (RMR) to be associated with superior weight loss maintenance from post-treatment to follow-up (but not from pre-treatment to follow-up) after controlling for fat-free mass (FFM) and fat-mass (FM). In addition, a higher follow-up RMR was significantly associated with superior weight loss maintenance after controlling for FFM, FM, and caloric intake. At follow-up, lower levels of dietary disinhibition and binge eating, greater levels of cognitive dietary restraint, greater internal locus of control, and less of a tendency to attribute weight to medical factors were all significantly correlated with superior weight loss maintenance. However, the psychological variables did not mediate the relationship between RMR and weight loss maintenance. Greater physical activity at post-treatment and follow-up was correlated with superior weight loss maintenance, but calorie and fat intake were not. The results suggest that RMR assessed at some point after a BWLP is generally associated with weight loss maintenance following treatment and that it is important to control for body size and caloric intake in such analyses. Therefore, helping participants to find ways to maximize RMR following weight loss may be important for long-term success. Results also indicate that psychological variables assessed during active weight loss maintenance may be better predictors of weight maintenance outcomes compared to the same factors assessed at earlier times. Finally, maintaining high levels of dietary control and physical activity may be key to increasing weight loss maintenance success. Weight loss maintenance efforts may benefit from viewing obesity as a mulifacted health concern with metabolic, behavioral and psychological underpinnings.