Objective This meta-analysis synthesized the findings from randomized controlled trials (RCTs) of motivational interviewing (MI) for health behavior outcomes within primary care populations. Methods Published and unpublished RCTs were identified using databases and online listservs. Studies were synthesized by outcome subgroup and meta-regression analyses were conducted to determine potential moderators accounting for heterogeneity within samples. Results Mean effect sizes ranged from .07 to .47; significant effect sizes were found for the adherence subgroup of studies (p = .04) and all outcomes combined (p = .02). Professional credentials of intervention deliverer were found to significantly moderate the association between MI and effect size in substance use subgroup (p = .0005) and all outcomes combined (p = .004). Conclusions Mean effect sizes were largest in outcomes related to weight loss, blood pressure, and substance use. MI appears to be useful in clinical settings and as few as 1 MI session may be effective in increasing change-related behavior on certain outcomes.

Obesity and binge eating disorder are detrimental health conditions that are associated with lower qualities of life. Individuals with obesity often face societal discrimination and frequently experience related medical disorders such as diabetes, hypertension, and hyperlipidemia. Current research suggests neurobiological similarities between obesity, binge eating disorder, and substance dependence. In addition, behavioral similarities link the two conditions; obese and substance dependent individuals often report similar features such as loss of control towards food or substances, respectively, and cravings. Treatment options for obesity have begun to use this information to formulate pharmacological and therapeutic interventions that may provide greater results for weight loss and decreased binge frequency. Similarly, treatment approaches to substance addictions should consider aspects of weight management. Findings from research and treatment studies are presented with the aim of reviewing the current literature of obesity within the context of an addiction framework and providing information on empirically supported approaches to the treatment of cooccurring obesity and substance addiction.