Associations of Problematic Smartphone Use and Smartphone Screen Time With Eating Disorder Psychopathology in Non-Clinical Samples: A Systematic Review.

Background: The ubiquitous use of smartphones has given rise to maladaptive patterns of use, often termed "problematic smartphone use" (PSU), which disproportionately impacts children and young people and is associated with poor mental health. Emerging evidence suggests that patterns of smartphone use (eg, PSU and high smartphone screen time) may also influence eating patterns and contribute to symptoms associated with eating disorders (ED), although the nature of this relationship remains poorly understood. Objective: The aim of this systematic review was to examine the association between PSU and ED psychopathology or ED-related outcomes (eg, body dissatisfaction, emotional eating, and food addiction) in clinical and nonclinical populations and explore potential moderators and mediators. Methods: This preregistered systematic review conducted according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines searched 3 databases (PubMed, Embase, and Web of Science) for studies published after January 2011 reporting data on PSU and ED psychopathology. Results: Thirty-five studies met the prespecified eligibility criteria, with almost all reporting cross-sectional data in nonclinical populations (n=52,584; mean age 17.0, SD 5.5 years). Most studies were assessed as being of good quality (n=28, 78%) according to a modified version of the Newcastle-Ottawa Scale. In these nonclinical samples, the vast majority of studies reported a positive association between PSU and ED psychopathology, which was largely consistent across age groups and countries. Identified mediators of this relationship included greater emotional regulation difficulties and anxious and depressive symptoms. Positive associations were also found across studies between PSU and several ED-related outcomes including food addiction, body dissatisfaction, uncontrolled eating, and emotional overeating. Daily smartphone screen time was consistently related to higher ED psychopathology. According to a GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) assessment of the evidence, most outcomes were rated as low certainty, largely due to the cross-sectional nature of evidence, which contributed to a high risk of bias. Conclusions: PSU and greater daily smartphone screen time are associated with higher ED symptoms, body image dissatisfaction, and broader disordered eating behaviors. Due to a paucity of studies in clinical populations, these conclusions are generalizable only to nonclinical populations (ie, those without a formal diagnosis of an ED). Further longitudinal research in clinical populations is needed to fully contextualize the impact of PSU and smartphone screen time on ED risk and severity.