High ambient temperatures associated with reduced anthropometric indicators in children from Sub-Saharan Africa

This systematic review and meta-analysis examined the association between high ambient temperatures and anthropometric indicators across 2,943,695 individuals, with a predominant focus on children under five years of age in Sub-Saharan Africa. The exposure was high ambient temperatures and heatwaves, with anthropometric indicators (height-for-age, weight-for-age, weight-for-height) serving as the primary outcome. The main results indicated an inverse relationship: for each 1°C increase in average temperature, Weight-for-Height Z-scores (WHZ) in children decreased by 0.12 standard deviations, and Height-for-Age Z-scores (HAZ) decreased by 0.03 standard deviations. Findings for other anthropometric outcomes in children were mixed but generally indicated an inverse relationship. In adults, elevated temperatures were associated with both underweight and obesity, suggesting complex effects on nutritional status.

Safety and tolerability data were not reported in the review. The analysis is limited by significant methodological heterogeneity across the included studies and a noted need for more longitudinal and geographically diverse research to strengthen the evidence base. The certainty of the evidence is tempered by these limitations and the modest effect sizes observed at the individual level.

In practice, these findings are relevant for informing evidence-based, climate-adaptive public health strategies aimed at mitigating potential nutritional consequences of rising temperatures. However, clinicians should interpret these results cautiously as they demonstrate an association, not causation. The population-level implications could be considerable given widespread exposure to heat, but the direct clinical application for individual patient management remains unclear and requires further investigation.