Association between determinants of weight status in children, 13-15 years in Bloemfontein

English: Introduction: Childhood obesity has become a major public health issue with children being heavier today than they were 20 years ago. This phenomenon is presently observed in both developed and developing countries. As a result of this childhood obesity epidemic, a number of chronic illnesses and risk factors for adult diseases are now beginning in childhood. Most studies conducted in South Africa only determined the prevalence of overweight and obesity, however few addressed the determinants of overweight and obesity in children. Objective: The main objective of this study was to determine the school environment as well as associations between dietary intake, socio-economic status, physical activity levels and weight status of children aged 13 – 15 years in Bloemfontein. Methodology: A representative sample of 415 children of different ethnic and socio-economic backgrounds participated in the study. Questionnaires were used to collect socio-economic, dietary intake, physical activity, and school environment data. Body mass index was calculated using weight and height measurements and waist circumference was measured. The quantitative food frequency questionnaire was used to determine dietary intake, and nutrient intake was analysed. Results: Weight status: Only a small percentage of the children were overweight and obese, with the girls being more overweight and obese than the boys. A statistically significant association was made between BMI and waist circumference. Socio-economic status: The association between socio-economic status and overweight and obesity was not significant, but the prevalence of overweight and obesity was higher in children with a high socio-economic status and lowest in children with a medium socio-economic status. No statistically significant association could be found between BMI and race. However, white children tended to be more overweight and obese than black and coloured children. School environment: Only a few schools reported having nutrition education programmes or campaigns. In most of these schools, the programmes were run only once a year and mostly by educators and not the learners themselves. None of the schools had vending machines on the school premises, but all schools reported having a tuckshop and/or hawkers on or around the school premises. The sale of healthier options of foods such as yoghurt, milk and whole-wheat bread was reported by few schools, while most schools reported selling less healthy options, including crisps, sweets and carbonated drinks. Dietary intake: Macro- and micronutrient intakes of the children were mostly within the adequate range. Fibre intake was below the requirements in most children and the intakes of calcium, folate and potassium were also below requirements. Most of the children had energy intakes equal to or above the estimated energy requirements. Slightly more boys than girls had energy intakes above the estimated energy requirements. No statistically significant association could be made between energy intake and dietary fat intake and BMI. Physical activity levels: Physical activity levels of the children were mostly moderate to vigorous. During the weekend the number of inactive children increased, and that of the vigorously active children decreased. The inactive group of children consisted of more girls than boys. Underweight children had a significantly higher metabolic equivalent value than the normal and overweight groups. No statistically significant association could be made between total number of television hours and BMI. In the category of children who were classified as moderately and vigorously active, statistically significantly more children were underweight compared to the overweight and the normal weight children during the week. Conclusion: Decreased energy intake and promotion of physical activity levels should form integral parts of any prevention program that focuses on childhood obesity. Childhood obesity prevention programmes require a joint multidisciplinary, multisectoral collaboration in order for them to be successful.