Childhood undernutrition, manifested as stunting, wasting, and underweight, remains a major public health challenge, particularly in low- and middle-income countries. In Zambia, the burden of undernutrition remains persistently high despite ongoing interventions. This study analyzed trends and determinants of nutritional status among children under five years using data from the Zambia Demographic and Health Survey (ZDHS) conducted in 2001, 2007, 2013–14, and 2018. The analysis assessed the prevalence of stunting, underweight, and wasting in children aged 0–59 months, using mean Z-scores and standard deviations. Logistic regression models were applied to identify key socio-demographic and health-related risk factors, with analyses performed in Python, accounting for survey design and weights.

Findings revealed a notable decline in malnutrition: stunting dropped from 45.6% in 2001 to 34.7% in 2018; underweight from 27.3% to 11.6%; while wasting remained stable at approximately 4%. Severe stunting and underweight also decreased significantly, whereas severe wasting fluctuated. Prevalence rates were higher when excluding children under six months (left-truncated data), suggesting possible protection from early infancy due to exclusive breastfeeding. Key predictors of malnutrition included low birth weight, poverty, regional disparities, and diarrheal episodes.

Despite progress, stunting remains a pressing concern. The higher rates observed in older infants point to the need for strengthened interventions targeting the postnatal period. Enhancing maternal and child health services, improving nutrition programs, and addressing poverty are critical to sustaining reductions in childhood malnutrition.

The authors have declared no competing interest.

The author(s) received no specific funding for this work.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Institutional Review Board (IRB)/Oversight Body: Demographic and Health Surveys (DHS) Program, ICF International Approval or Exemption: Ethical approval for the Zambia Demographic and Health Surveys (ZDHS) was obtained by the DHS Program and the relevant national ethics committees in Zambia prior to data collection. The data used in this study are publicly available and de-identified, and this secondary analysis was exempt from further IRB review.

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