Effect of Sedentary Behavior on the Nutritional Status of Children (Age Between 6 to 12 Years)

Background: Sedentary behavior, prolonged screen exposure, inadequate physical activity, and unhealthy dietary practices are increasingly associated with abnormal nutritional status among school-aged children. In urban settings such as Karachi, these behaviors may contribute to both excess body weight and broader nutritional imbalance. Objective: To assess the association between sedentary behavior and nutritional status among children aged 6–12 years in Karachi, Pakistan. Methods: This school-based cross-sectional study included 380 children aged 6–12 years from selected public and private schools in Karachi. Data were collected using a structured parent-completed questionnaire assessing sociodemographic characteristics, dietary behaviors, physical activity, sedentary behavior, screen time, sports participation, and transport mode. Height and weight were measured using standardized procedures, and nutritional status was classified using WHO BMI-for-age Z-score categories. Data were analyzed using SPSS version 23. Frequencies and percentages were calculated, and chi-square tests were used to assess associations between categorical variables and BMI-based nutritional status. Results: Of 380 children, 201 were male and 179 were female. Overall, 43 children were underweight, 124 had normal weight, 79 were overweight, and 134 were obese. Combined overweight/obesity was present in 213 children. Weekday sedentary behavior, recreational screen time >2 hours/day, physical activity category, breakfast frequency, dinner frequency, fast-food and snack intake, delayed meal pattern, and transport mode were significantly associated with BMI-based nutritional status. Screen time >2 hours/day showed the clearest association with overweight/obesity, as 170 of 195 children in this category were overweight or obese compared with 43 of 185 children with screen time ≤2 hours/day. Conclusion: Sedentary behavior, prolonged recreational screen time, dietary patterns, and physical activity category were significantly associated with nutritional status among children aged 6–12 years in Karachi. Because of the cross-sectional design, the findings should be interpreted as associations rather than causal effects. School- and family-based interventions should prioritize reducing recreational screen exposure, promoting regular physical activity, and improving dietary routines.