Digital exposure and health behaviours in adolescents: a cross-sectional study from South India

Adolescence is a critical developmental period during which lifestyle behaviours such as diet, physical activity, and screen use are established. Increasing screen exposure and changing lifestyle patterns have raised concerns regarding their impact on health outcomes. This study aimed to assess eating behaviour, physical activity, and screen time among adolescents and examine their association with demographic factors in a school-based setting in South India.

A cross-sectional descriptive study was conducted among adolescents aged 12-15 years using a purposive sampling technique. Data were collected using structured questionnaires, including a sociodemographic proforma, Johnson Adolescent Food Habits Checklist, Physical Activity Questionnaire, and Questionnaire for Screen Time (QueST). Statistical analysis was performed using SPSS version 29.0, and associations were assessed using chi-square tests with significance set at p-value < 0.050.

Total of 192 adolescents were included. Most adolescents demonstrated neutral eating behaviour (93.2%). Physical activity classification revealed that 54.7% of participants were highly active, 44.8% reported low physical activity, and 0.5% (n = 1) were moderately active. Screen exposure was reported across academic and recreational domains. Across the screen-time domains, 14.1%-20.3% reported screen exposure of 2 h or more per day. Significant associations were observed between physical activity and sex (p-value = 0.006), family type (p-value = 0.015), exercise status (p-value = 0.018), and age (p-value < 0.050). Eating behaviour was significantly associated only with type of food (p-value = 0.029). Screen time showed no significant association with most demographic variables, except for age, which was significantly associated with increased screen exposure in specific domains.

This study found that most adolescents had eating-behaviour scores in the intermediate range, physical activity levels were mainly divided between low and high activity, while screen use was reported across both academic and recreational domains, with 14.1%-20.3% of adolescents reporting in excess of two hours per day. Physical activity was significantly associated with sex, family type, exercise status, and age, whereas eating behaviour was associated with type of food. Screen time was associated with age only in the studying and entertainment domains. Collectively, these findings elucidate the need for school-based health promotion strategies, encompassing regular physical activity programmes, nutrition education oriented towards balanced meal routines, and age-sensitive screen-time management guidance addressing both academic and recreational digital engagement.