Social Media and Children's and Adolescents’ Diets: A Systematic Review of the Underlying Social and Physiological Mechanisms

The association between social media (SM) and children's and adolescents’ diet is poorly understood. This systematic literature review aims to explore the role of SM in children's and adolescents’ diets and related behaviours considering also the underlying mechanisms. We searched Medline, Scopus and CINAHL (2008-December 2021) for studies assessing the relationship of SM exposure with food intake, food preference, dietary behaviours and the underlying mechanisms (e.g., brain activation to digital food images- as proxy for SM food images) among healthy children and adolescents aged 2–18 years. The protocol was registered in PROSPERO (number: CRD42020213977). A total of 35 articles were included. Of four studies, one found that exposure to peers’ videos on healthy eating, but not SM-influencers’, increased vegetable intake. Most studies reported that SM was associated with skipping breakfast, increased intake of unhealthy snacks and sugar-sweetened beverages, and lower fruit and vegetable intake, independent of age. Children and adolescents exposed to unhealthy vs. healthy digital food images showed increased brain response in reward- and attention-related regions. The mechanisms underpinning the abovementioned associations were: i) physiological (appetitive state, increased neural response to portion size and energy density of food depicted), and ii) social (food advertising via SM-influencers and peers). SM exposure leads to unfavourable eating patterns both in children and adolescents. The identified mechanisms may help to tailor future health interventions. Down-regulating SM advertising and limiting SM exposure to children and adolescents may improve food intake and subsequent health outcomes.