Interactive influences of food, contexts and neurocognitive systems on addictive eating

Compulsive eating is a common symptom of different conditions, including obesity, binge eating disorder and bulimia. One hypothesis is that contemporary food products promote compulsive eating via addiction-like mechanisms. However, what is the addictive substance in food, and what is the phenotypic overlap between obesity / eating disorders and addictions are questions that remain unresolved. In this review, we applied a multilevel framework of addiction, which encompasses the 'drug' (certain foods), the person's mindset, and the context, to improve understanding of compulsive eating. Specifically, we reviewed evidence on the addictive properties of specific foods, the neurocognitive systems that control dietary choices, and their interaction with physical, emotional and social contexts. We focused on different target groups to illustrate distinct aspects of the proposed framework: the impact of food and contextual factors were examined across a continuum, with most studies conducted on healthy participants and subclinical populations, whereas the review of neurocognitive aspects focused on clinical groups in which the alterations linked to addictive and compulsive eating are particularly visible. The reviewed evidence suggest that macronutrient composition and level of processing are associated with the addictive properties of food; there are overlapping neuroadaptations in reward and decision-making circuits across compulsive eating conditions; and there are physical and social contexts that fuel compulsive eating by exploiting reward mechanisms and their interaction with emotions. We conclude that a biopsychosocial model that integrates food, neurobiology and context can provide a better understanding of compulsive eating manifestations in a transdiagnostic framework.