Overeating, Overweight, and Substance Use: What Is the Connection?

Abstract

This paper integrates recent developments in the areas of excessive eating and addictive behavior, reviewing shared and unique features with respect to topography, etiological mechanisms/risk factors, comorbidity, and related adverse consequences/correlates. Emerging literature is converging to suggest a high degree of overlap in terms of eating and addictive behavior, including common risk factors and involvement of brain reward pathways. Behavioral phenotypes involving putative addictive elements include binge eating, food addiction, nocturnal eating, grazing, and emotional eating. Emerging evidence supports that dysregulation of brain reward pathways may underlie certain forms of obesity, particularly when driven by compulsive eating behavior or binge eating disorder/food addiction, and the evidence for comparable dysregulation underlying substance use disorders (SUD) and other addictive behavior is quite robust, with a high degree of overlap in brain circuitry driving excessive eating and drug addiction. At least one form of weight loss (bariatric) surgery, Roux-en-Y gastric bypass, is associated with post-surgical SUD onset, and this body of work has greatly expanded our appreciation of the intricate gut-brain connections involved in eating and addictive behavior. Nonetheless, controversy remains regarding the extent to which and in what forms eating behavior may constitute addiction. Research productivity in the intersection of eating, obesity, and addiction has increased dramatically over the past decade, particularly within the past 5 years; it is expected that our understanding of these relationships will grow substantially in the coming years, particularly in light of recent advances in our understanding of the nuances of gut-brain communication that may shed light on new mechanisms.