Dietary diversity and child malnutrition in Ghana: a nationally representative analysis of socioeconomic gradients and effect modification.

Abstract

Inadequate dietary diversity during complementary feeding contributes to high childhood malnutrition rates in sub-Saharan Africa. Understanding relationships between dietary quality and nutritional outcomes across socioeconomic subgroups is essential for designing effective, equitable interventions. We examined associations between dietary diversity and nutritional status among children aged 0-23 months in Ghana, with attention to effect modification by socioeconomic factors. We analysed data from 2031 children Ghana Demographic and Health Survey 2022 Dietary diversity was assessed using the WHO minimum dietary diversity indicator (≥5 of 7 food groups consumed in 24 hours). Nutritional status was evaluated through WHO z-scores; stunting, wasting and underweight were defined as z-scores below -2 SD. Survey-weighted multivariable logistic regression examined associations adjusting for child, maternal, household and geographic factors. Sensitivity analyses included prevalence ratios from modified Poisson regression, an 8-food-group minimum dietary diversity definition and models with region and additional covariates. Stratified analyses tested effect modification. Only 28.3% of children aged 6-23 months achieved minimum dietary diversity, with disparities by wealth (20.8% poorest vs 47.6% richest) and maternal education (16.6% no education vs 57.1% higher education). Stunting affected 14.8% of children overall, increasing with age. In fully adjusted models, minimum dietary diversity was associated with a 42% reduction in underweight odds (OR=0.58, 95% CI 0.37 to 0.91, p=0.018). Wasting showed a consistent protective direction (OR=0.63, 95% CI 0.36 to 1.11, p=0.110), reaching significance with the 8-food-group definition (OR=0.51, p=0.012) and in dose-response analysis (OR=0.86 per food group, p=0.018). No association was observed for stunting (OR=1.09, 95% CI 0.73 to 1.63, p=0.678). Dose-response patterns were evident for underweight (OR=0.88 per food group, p=0.021) and wasting (OR=0.86, p=0.018). Exploratory stratified analyses suggested stronger protective associations among children of mothers with lower education, though formal interaction tests were non-significant. Dietary diversity is associated with reduced acute malnutrition among Ghanaian children, particularly underweight, with suggestive evidence for wasting. The null finding for stunting is consistent with the multifactorial, cumulative aetiology of chronic malnutrition. Findings support incorporating dietary diversity improvement into equity-focused nutrition strategies while recognising that addressing stunting requires broader multi-sectoral approaches.