Virtual Worlds versus Real Body: Virtual Reality Meets Eating and Weight Disorders

This Special Issue presents and discusses a collection of authoritative studies suggesting that computergenerated graphic environments—virtual reality (VR) and augmented reality (AR)—can integrate and extend existing prevention, assessment, and treatment protocols for eating and weight disorders (EWDs). The diffusion of EWDs is a worldwide problem. In the United States alone, 20 million women and 10 million men suffer from a clinically significant eating disorder during their lifetime. For obesity, the situation is even worse. According to the data recently collected by the Gallup Organization in the Gallup-Healthways Well-Being Index (GHWBI), the U.S. adult obesity rate in 2013 was 27.2%. EWDs have serious consequences for individuals and a significant economic impact on health systems. In addition to the direct consequences for the health of individuals, these disorders may contribute, directly or indirectly, to severe disability and premature death. Apparently, both problems have a simple explanation: an imbalanced energy regulation. In obesity, energy intake exceeds energy expenditure; in anorexia, energy intake is lower than energy expenditure. However, their prevention and treatment is still an open challenge. In its Weight Control Information Network, the U.S. National Institutes of Health discusses the etiology of obesity in this way: ‘‘Energy balance is a fundamental principle of physics that regulates weight gain and loss. However, even when admitting that the main cause of obesity is an inadequacy between energy intake and expenditure, there remains a lot to be learned in order to properly manage the epidemic. Research is barely shedding light on the mysteries of this complex disorder’’ (http://win.niddk.nih.gov/publications/ understanding.htm#whatcausesobesity). The situation is not so different for anorexia. As underlined by Fairburn and Harrison in their review article published in The Lancet: ‘‘virtually nothing is known about the individual causal processes involved, or about how they interact and vary across the development and maintenance of the disorders.’’ A similar view is expressed by Kaye et al. in their Nature Review Neuroscience article 6 years later: ‘‘Anorexia nervosa is a disorder of unknown etiology.’’ The actual situation is pushing obesity and eating disorder researchers to begin a collaboration. In particular, their common effort is focused on the identification of risk factors that are shared between these disturbances: apparently, stress and unhealthful weight-control behaviors—such as fasting (going without eating for 24 hours for weight control), vomiting, or laxative abuse—are the common antecedents of both obesity and eating disorders. More, an open challenge is the quest for improving the effectiveness of the available evidence-based interventions. This Special Issue will focus on the two leading virtual technologies—augmented reality (AR) and virtual reality (VR)—exploring their clinical potential for EWDs. As suggested by many studies, these technologies may have a big impact on clinical practice for the high level of selfreflectiveness and personal efficacy induced by their emotional engagement and sense of presence: if AR adds virtual information to the real world, VR completely replaces the real environment with a virtual one. Recent studies, summarized in the review by Wiederhold et al. opening this Special Issue, indicate that VR and AR can integrate and extend existing prevention, assessment, and treatment protocols for EWDs. The first section of the Special Issue showcases the potential of VR in supporting and improving health behavior change for the prevention and treatment of EWDs. In their study, Behm et al. present and discuss the potential of a social virtual world (Second Life) for increasing health self-efficacy (exercise and nutrition efficacy) among overweight adults. Their results suggest that for users who like video game VR are able to improve exercise efficacy and to support weight loss. A similar result is reported in the article by Kuo et al.: compared with control participants, participants who viewed their weight-reduced avatars ate less ice cream in a taste test and were more likely to choose a sugar-free drink as a reward. These articles confirm the Proteus effect—the behavior of an individual conforms to his/her digital self-representation—and underline the significant potential of VR in behavioral modeling. As underlined by Fox and Bailenson, using VR ‘‘we have the capability to create ideal self-models that can motivate