Association of Junk Food Consumption, Daily Screen Time and Daily Physical Activity with Overweight and Obesity among School Children Aged 8-10 Years- A Cross-sectional Case-control Study

Introduction: The prevalence of obesity among school children in Kerala is on a steady rise. Consumption of food with high glycaemic index, change in sleep patterns, reduced physical activity and the use of screen has been linked to obesity in children. Published literature on this association is scarce from urban Thiruvananthapuram, hence, the present study. Aim: To identify the association of various risk factors such as frequency of junk food consumption, dietary preferences, physical activity and daily screen time and weight related disorders among school going children (8-10 years) in Thiruvananthapuram. Materials and Methods: The present cross-sectional casecontrol study was conducted in one Rural Government School (Venjaramoodu Government Upper Primary School) and one Urban Private School (S.N. Public School, Chenkottukonam) of Thiruvananthapuram, Kerala, India, and enrolled school going children aged 8-10 years with higher than recommended Body Mass Index (BMI) for age as cases, age and gendermatched children with normal BMI as controls. Participants with BMI above 23rd and below 27th adult equivalent for age and gender were considered overweight and those above 27th adult equivalent for age and gender were considered as obese. A structured questionnaire was sent home with the children, and the parents were requested to answer the questions along with written informed consent. Socio-demographic parameters, anthropometric measurements were obtained by trained staff, dietary habits, and details regarding physical activity and screen usage were collected. Variables were categorised according to the standard recommendations by World Health Organisation (WHO) and Indian Association of Paediatrics (IAP). Variables were expressed as frequencies and the tests of significance used were Chi-square test and Odds ratio, to express the strength of association between parameters. A p-value <0.05 was considered statistically significant. Results: The mean age of cases and controls was nine years. A total of 708 school children were screened and 352 participants (175 cases and 177 controls) were enrolled in the present study. The BMI of cases was 29.3 kg/m2 and of controls was 20.2 kg/ m2 . Higher than recommended screen time (p<0.001), more frequent junk food consumption (p<0.001) and lack of physical activity (p<0.001) were found to be significantly associated with obesity and overweight. Dietary preference was not associated with obesity or overweight and obesity and overweight was more common in children studying in private schools (p<0.001). Conclusion: Reducing screen time, reducing junk food consumption and increasing physical activity will help in reducing the prevalence of life style diseases among school children. Further evaluation is necessary to determine the factors contributing to the increased prevalence of these disorders in private schools.