Association between unhealthy food consumption and mental health outcomes in children and adolescents: an umbrella review

The consumption of unhealthy food has increased substantially among children and adolescents across the globe. This umbrella review aims to synthesize meta-analyses that assess unhealthy food consumption and mental health outcomes in children and adolescents. The protocol was pre-registered with PROSPERO (CRD42023475965). We searched PubMed/MEDLINE, Scopus, Embase, and CINAHL from inception through January 2025 for meta-analyses that estimated associations between unhealthy food exposures and mental health in children and adolescents (< 19 years). Exposures included ultra-processed food (UPF), junk food, World Health Organization unhealthy food indicators (e.g., sweets), and Western dietary pattern. Extracted meta-analyses were replicated, re-evaluated for credibility, and assessed for methodological quality. With a sum total sample size of 2,526,232, our search yielded 15 pooled estimates. Convincing evidence (Class I) linked higher UPF consumption to short sleep duration (odds ratio = 1.30, 95% CI [1.26, 1.33]) and insomnia (odds ratio = 1.47, 95% CI [1.37, 1.57]). Highly suggestive evidence (Class II) related higher UPF consumption to poor sleep quality (odds ratio = 1.53, 95% CI [1.46, 1.60]), and common mental disorders (odds ratio = 1.53, 95% CI [1.44, 1.63]), and higher junk food consumption to depression (odds ratio = 1.62, 95% CI [1.39, 1.90]). Suggestive (Class III) or weak (Class IV) evidence related junk food to anxiety and stress, and junk food, sweets, and Western dietary patterns to attention-deficit/hyperactivity disorder. Associations with sleep dissatisfaction and happiness were not statistically significant. Findings suggest that children and adolescents who eat more unhealthy food tend to have poorer mental health. Nutrition-based interventions should prioritize children and adolescents since this population may be particularly susceptible to diet-related poor mental health. Further causal-inference studies should evaluate whether lowering consumption improves youth mental health.