Smartphone usage in young adults: cross-sectional associations with physical activity, sleep, social isolation, academic achievement, and anxiety

High-risk smartphone use was linked to social isolation and poorer sleep quality, indicating negative effects on mental and physical health. Anxiety was identified as a statistically significant correlate of smartphone addiction scores in the regression analysis, suggesting emotional dysregulation plays a central role. High-risk smartphone users were also less physically active and more sedentary, though this was not directly tied to addiction scores.