Smartphone use health outcomes in children and adolescents: A systematic review of behavioral, developmental, and environmental risk pathways

Figure 5 Mechanistic pathway linking excessive smartphone use to childhood obesity. This conceptual diagram illustrates a sequential pathway whereby excessive smartphone exposure (≥ 2-3 hours/day, ≥ 6 hours/day, or problematic/addictive use) promotes physical inactivity characterized by reduced moderate-to-vigorous physical activity, increased sedentary behavior, shortened sleep duration, and increased energy-dense snacking. These behavioral shifts result in positive energy balance (↑ energy intake, ↓ energy expenditure), contributing to metabolic dysregulation, including insulin resistance, visceral adiposity, systemic low-grade inflammation, and dyslipidemia. Sustained metabolic alterations promote adipose tissue accumulation, increased body mass index and waist circumference, and progression to overweight and obesity, ultimately elevating long-term cardiometabolic risk. BMI: Body mass index.