Trends and Factors Associated with Stunting and Underweight among Early Grade Learners in Low-Quintile Schools in Johannesburg, South Africa (2020–2022)

Background Although South Africa has made progress in reducing child undernutrition over the last three decades, most data are aggregated at national or provincial levels and are focused on children under five. Limited attention has been given to early grade learners (ages 5–9), particularly in urban low-income settings. This study examines trends and determinants of stunting and underweight among early-grade learners in low-quintile schools in Johannesburg from 2020 to 2022. Methods A longitudinal study design of the Community of Practice (CoP) for Child Wellbeing was employed. Data were collected over three waves on a matched sample of 129 learners across the selected five no-fee primary schools in Johannesburg. Anthropometric measurements were used to assess stunting and underweight. Data were analyzed at three levels: univariate, bivariate, and multivariate. The Chi-square test of association and multivariable logistic regression analysis were conducted to identify predictors of nutritional outcomes. Results The prevalence of stunting declined from 14% in 2020 to 10% in 2022, while the prevalence of underweight rose from 6% to 12%. Male learners were significantly more likely than females to be both stunted (aOR=3.41, 95% CI: 1.00–11.56) and underweight (aOR=5.08, 95% CI: 1.04–24.70). High levels of caregiver depression (70.54%) and food insecurity were observed but not significantly associated with child nutrition status in adjusted models. Discussion This study demonstrates that while progress has been made in reducing stunting among early grade learners, rising underweight rates, especially among boys, signal new forms of acute vulnerability linked to household food insecurity and COVID-19–related shocks. Conclusion The rising trend in underweight, particularly among boys, signals increasing acute nutritional vulnerability among early grade learners in urban low-quintile schools. Despite some gains in reducing stunting, current interventions do not adequately address children’s nutritional needs.