Thesis (MTech (Biomedical Technology))--Cape Peninsula University of Technology, 2008 / Epidemiological reports have shown that South Africa, whilst a developing country, irs overweight and obesity prevalence rates in children is fast approaching those seen in the developed world. This country's population is unique in that it is made up of different ethnic groups with different socia-economic status, partly due to the past and present political environments in the country. South Africa, in particular, is faced with a rapid increasing childhood obesity of 10% among children under the age of two and 5-20% among those less than six years of age. The prevalence of obesity is increasing in children of all ages and represents the complex integration of genetic, behavioural and environmental influences. The Ectonucleotide Pyrophosphatase Phosphodiesterase 1 (ENPP1) gene is located on chromosome 6q22-q23; a locus linked to obesity and diabetes, spans 83 kb of genomic DNA and contains 25 exons. Studies in humans have shown a correlation between overexpression of ENPP1 and insulin resistance, obesity, and type 2 diabetes. ENPP1 has been implicated in up to 20% of Caucasian and 50% of Black communities suffering from obesity. The overall objective of the proposed study is to assess whether ENPP1 polymorphisms contribute to childhood obesity/overweight, and their association with components of metabolic syndrome in a South African Coloured population. Subjects for this study were identified through a screening program that aimed to determine the prevalence of obesity in learners between the ages of 8 - 18 years from the Western Cape Province, South Africa. The first phase of the project was to clearly differentiate between obese subjects and controls. The cut-off points for obesity established by Cole and co-workers in 2000, and adopted by the International Obesity Task Force (IOTF), were used to classify the obese subjects.

The aim of the study was to determine the Body Mass Index with regards to overweight and obesity of Black African children between the ages of six and nine years who were enrolled in three rural public schools within Mpumalanga Province, South Africa. The researcher used a quantitative descriptive research design. Each child’s weight and height was measured and their BMI and BMI percentile for gender and age calculated. According to the BMI percentile calculations for gender and age for the sample which consisted of 902 children, three percent were defined as being underweight, 79 percent as being normal weight, 11 percent as being overweight, and seven percent as being obese. In the sample there were also 21.3 percent children who were at risk of becoming overweight (3.5 percent) and obese (17.8 percent). Without intervention these at risk learners may in their adolescent and adult years be adversely affected by the physiological and psychosocial consequences related to their condition. Suggestion is made to utilise a Forum through which various stakeholders can pool their expertise and resources to develop a programme of intervention with the aim to prevent escalation of overweight and obesity, as well as reversing the current prevalence as identified within the research population.

Background: Obesity is a chronic and complex metabolic disease with associated comorbidities. The prevalence of excess body weight has risen substantially in both affluent developed countries and in developing countries worldwide. In 2008 it was estimated that 43 million children under the age of five were overweight, with developing countries accounting for 75 percent of these rates. Furthermore, with 75 percent of these children developing adulthood obesity, mortality rates due to obesity will continue to increase unless preventative interventions are implemented. Objective: To identify the prevalence of obesity and overweight among urban seven to 10 years old children in Quintile five English-medium schools in the Nelson Mandela Metropolitan municipality in the Eastern Cape, South Africa. Design and Methods: A quantitative descriptive one-way cross-sectional research design utilising random sampling was used. A total of 713 children participated in the study. A onceoff survey consisted of anthropometrical assessment of height, weight and waist circumference. To classify children into weight categories, the International Obesity Task Force cut-off values were used. A validated physical activity – related behaviour questionnaire was completed to explore and identify the daily level of physical activity expressed in MET values. Using one-way ANOVA’s and Chi-squared tests, significance between variables was analysed. Results: Overweight prevalence was 20.9 percent and obesity prevalence was 9.8 percent. A significant relationship was found between obesity and overweight levels for gender, age, ethnicity and culture. No significant relationship was found for obesity and overweight prevalence and physical activity. Conclusion: Results highlight the rising prevalence of obesity and overweight amongst urban children from affluent primary schools and the necessity for further research to explore sociocultural factors that impact on obesogenic behaviour in South African youth.

Aim: To determine whether the tuck shop purchasing habits of Grade 4 learners were contributing towards the development of childhood overweight and obesity. Objectives: To assess the nutritional quality of the food and beverages available for learners to purchase; items regularly purchased from the tuck shop as well as factors influencing the learner’s decision to purchase these items; the anthropometric and socio-demographic characteristics of grade 4 learners as well as their nutrition knowledge related to the tuck shop items purchased. Method: A survey administered to 11 tuck shop managers, a questionnaire administered to 311 Grade 4 learners and two single-sex focus groups of 5 learners each were conducted. Results: Fifty six percent of the sample were female (n=173) and 44% were male (n=138). Twenty seven percent of the study sample was overweight (n = 83) and 27% were obese (n = 85). Eighty six percent of learners (n = 266) claimed to buy from their school tuck shop. Twenty two percent of learners purchased from their tuck shop at least three times per week (n =58). Learners who purchased from the tuck shop had a significantly higher BMI than those who did not (p = 0.020). Learners who purchased from the tuck shop spent on average R8,38 per day with a minimum of R1 and a maximum of R40 (standard deviation R5.39). The most popular reasons for visiting the tuck shop included “this is my favourite thing to eat or drink” (66.5%, n = 177) and “I only have enough money to buy this item” (47.0%, n = 125). Savoury pies were the most popular "lunch" item for all learners for both food breaks (45%, n = 5 schools and 27.3%, n = 3 schools) selling the most number of units (43) per day at eight of the eleven schools (72.7%). Iced popsicles were sold at almost every school, ranked as the cheapest beverage and also sold the most number of units (40.7). Healthy beverages sold included canned fruit juice and water, while healthy snacks consisted of dried fruit, fruit salad, bananas, yoghurt and health muffins. The average healthy snack contained almost half the kilojoules of its unhealthy counterpart (465kJ vs 806kJ). Nutritional analyses of the healthy lunch options revealed total fat contents that exceeded the DRI and South African recommended limit. Perceived barriers to stocking healthy items included cost and refrigeration restrictions. The average score for the food groups was only 33% indicating that learners were not familiar with the Food Based Dietary Guidelines (FBDG). Further analyses showed that the total knowledge scores of those learners that reported to buy from the tuck shop frequently, was significantly lower when compared to the total knowledge scores of those learners who bought from the tuck shop less frequently (13.0 ± 3.9 and 11.6 ± 3.1, respectively; p < 0.05). Logistic regression analysis confirmed that the total knowledge of a learner could be used to predict whether he or she is more likely to make purchases from the tuck shop (significance = 0.017). Focus group results revealed that learners are aware of “healthy” and “unhealthy” tuck shop items. Most learners stated that they would continue to purchase items from their tuck shop if all “unhealthy” items were removed. Conclusion: Primary school tuck shops of well resourced schools in Pietermaritzburg are contributing to childhood overweight and obesity through a combination of factors. These include the poor nutritional quality of the items stocked at the tuck shop as well as the poor tuck shop purchasing practices. Much consultation is required amongst dieticians, school principals and privatised tuck shop managers to overcome barriers to stocking healthy items. School management and government have an important role to play in imposing restrictions on the sale of unhealthy items; along with improving the quality of the nutrition education curriculum to ensure that learners are able to translate their knowledge into healthier purchasing practices. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.

MPH / Department of Public Health