Peer-reviewed article
Child wasting and concurrent stunting in low- and middle-income countries
Andrew N. Mertens, Jade Benjamin‐Chung, John M. Colford, Alan Hubbard, Mark J. van der Laan et al. ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This study analysed 21 longitudinal cohorts from low- and middle-income countries to understand how child wasting develops and resolves over time. Wasting is far more common than single-point measurements suggest, with nearly 30% of children experiencing at least one wasting episode by age 24 months, compared to only 5.6% appearing wasted at that single time point. Children who become wasted early (before 6 months) recover faster but face higher risks of later growth faltering and stunting. The research shows that seasonal rainfall patterns affect child nutrition substantially, suggesting that timing interventions to match these seasons could be more effective.
Key points
- Wasting incidence peaks between birth and 3 months of age
- By age 24 months, 29.2% of children had experienced at least one wasting episode and 10.0% had experienced two or more episodes, compared to 5.6% measured as wasted at a single point in time
- Early wasting (before 6 months) leads to faster recovery but increases risk of later concurrent wasting and stunting
- Population average weight-for-length z-scores varied by more than 0.5 z-score in some cohorts, with lowest mean z-scores during rainiest months
- Current programmes focusing on children aged 6-59 months miss a critical prevention opportunity in the 0-6 month period
Limitations
The study does not evaluate the effectiveness of specific interventions to prevent wasting, so it cannot demonstrate which prevention or treatment approaches actually work. The analysis is observational and describes patterns across cohorts rather than testing causal mechanisms or intervention outcomes.
Abstract
. Prevailing methods to measure wasting rely on cross-sectional surveys that cannot measure onset, recovery and persistence-key features that inform preventive interventions and estimates of disease burden. Here we analyse 21 longitudinal cohorts and show that wasting is a highly dynamic process of onset and recovery, with incidence peaking between birth and 3 months. Many more children experience an episode of wasting at some point during their first 24 months than prevalent cases at a single point in time suggest. For example, at the age of 24 months, 5.6% of children were wasted, but by the same age (24 months), 29.2% of children had experienced at least one wasting episode and 10.0% had experienced two or more episodes. Children who were wasted before the age of 6 months had a faster recovery and shorter episodes than did children who were wasted at older ages; however, early wasting increased the risk of later growth faltering, including concurrent wasting and stunting (low length-for-age z-score), and thus increased the risk of mortality. In diverse populations with high seasonal rainfall, the population average weight-for-length z-score varied substantially (more than 0.5 z in some cohorts), with the lowest mean z-scores occurring during the rainiest months; this indicates that seasonally targeted interventions could be considered. Our results show the importance of establishing interventions to prevent wasting from birth to the age of 6 months, probably through improved maternal nutrition, to complement current programmes that focus on children aged 6-59 months.