Prevalence of overweight, obesity and central adiposity among grade seven adolescents in urban Tshwane, South Africa.

BACKGROUND

The global increase in overweight and obesity among adolescents is a significant public health priority, especially in low- and middle-income countries. In South Africa, urbanisation and lifestyle changes have exacerbated this challenge, but there is a lack of disaggregated data available to inform effective local responses.

AIM: To assess and describe the prevalence of overweight, obesity and central adiposity in Grade seven adolescents in urban Tshwane, South Africa, and explore its association with socioeconomic characteristics.

SETTING

The study was conducted in five diverse fee-paying public primary schools in urban Tshwane, Gauteng province.

METHODS

A quantitative, descriptive cross-sectional design recruited 164 adolescents aged 11-14 years. Anthropometric measures were performed according to World Health Organization (WHO) standards. These included a survey of height and weight to derive body mass index (BMI-for-age) z-scores, as well as waist circumference to height ratio (WHtR). Socioeconomic status was assessed using the validated Family Affluence Scale. Data analysis included descriptive statistics and chi-square tests to determine the association between categorical variables.

RESULTS

The combined prevalence of overweight and obesity was 23.7%, with a greater burden among girls (36.4% of 12 year olds) compared to boys (16.7%). The risk of central adiposity (WHtR ≥ 0.5) was found in 25% of participants, with 7.3% at very high risk. Household income was significantly associated with obesity (p = 0.043), while parental education was not statistically significant.

CONCLUSION

The high prevalence of excess adiposity, particularly among female adolescents, indicates an emerging cardiometabolic risk profile among the group.

CONTRIBUTION: This study addresses a critical gap in South African public health literature by providing locally specific, disaggregated data on the nutritional status of urban adolescents in Tshwane, a cohort that is underrepresented in contrast to conventional rural or national surveys.