Background: Smartphones, computers, and other digital devices have significantly contributed to extending screen time for adolescents and young adults. Too much screen time is recognized as a public health problem, with negative psychological, physical, and social health consequences.

Objective: To explore the relationship between screen time behaviour and psychological, physical and social health outcomes in 17-19-year-old college students.

Methods: The study adopted a quantitative cross sectional method of analysis using a sample of 200 college students (17- 19 years) in a selected college in Chennai, Tamilnadu, India. Simple random sampling was used for selection of the sample. The socio-demographic questionnaire, the Depression Anxiety Stress Scale (DASS-21), the Pittsburgh Sleep Quality Index (PSQI) and the Physical Activity Questionnaire for Adolescents (PAQ-A) were used to collect data. The data was analysed with IBM SPSS Statistics. Descriptive statistics, Pearson correlation, multiple regression and mediation analyses were conducted, and p < 0.05 was considered significant.

Results: Participants identified a significant amount of time spent on digital devices each day, with the majority of the time dedicated to social media. A significant number of participants exhibited moderate levels of depression, anxiety, and stress. Common symptoms were having poor quality of sleep, lack of physical activity, eye strain, headache, fatigue, neck pain, and back pain. Pearson correlation analysis revealed higher significant positive correlations between the psychological distress, poor sleep quality and social isolation with screen time behaviour and significant negative correlation with physical activity. Multiple regression analysis revealed that screen time behaviour was the most significant predictor of psychological health and associated with sleep quality and physical activity. Results of mediation analysis showed that sleep quality and physical activity partially mediated the relationship between screen time behavior and psychological health.

Conclusion: Increased screen time behaviour was associated with poorer psychological, physical, and social health outcomes among college students. Promoting healthy digital habits, improving sleep quality, and encouraging regular physical activity may help reduce the adverse effects of excessive screen time and support better overall well-being.