Dietary diversity and the triple burden of malnutrition among children aged 6–23 months in 62 low- and middle-income countries: an analysis of Demographic and Health Surveys

Background: The 2021 World Health Organization and United Nations Children's Fund definition of minimum dietary diversity (MDD) includes breast milk as an eighth food group. However, cross-country evidence under this revised definition remains limited. We estimated MDD achievement among children in low- and middle-income countries (LMICs) and examined its associations with anaemia, stunting, underweight, and overweight/obesity (OWOB). Methods: We analysed the most recent Demographic and Health Survey completed between 2000 and 2023 in 62 LMICs, comprising 123,569 children aged 6-23 months. We constructed MDD from standard DHS recode food-consumption variables according to the 2021 WHO/UNICEF definition, with achievement defined as consumption of at least five of eight food groups in the previous 24 hours. We estimated associations using survey-weighted logistic regression with country fixed effects and prespecified covariates. Complementary analyses included restricted cubic splines, a two-stage individual-participant-data meta-analysis, and ecological analyses. Results: Overall, 27.0% of children achieved MDD and 73.0% did not, with rates increasing from 17.7% in low-income countries to 42.9% in upper-middle-income countries. Binary MDD achievement was associated with lower odds of stunting across income groups (adjusted odds ratio (aOR) ranging from 0.677 to 0.822) and underweight (aOR ranging from 0.695 to 0.782). Continuous-score and categorical analyses showed similar patterns, whereas individual-level with anaemia and OWOB were not consistent. National MDD prevalence was inversely correlated with stunting (weighted R = -0.686; P < 0.001), underweight (weighted R = -0.678; P < 0.001), and anaemia (weighted R = -0.373; P = 0.003), but not with OWOB (weighted R = 0.068; P = 0.597). Conclusions: In our study, MDD achievement was low across 62 LMICs and varied substantially across countries and by urban or rural residence and household wealth. Greater dietary diversity was associated with lower odds of stunting and underweight across the primary income-stratified models, whereas individual-level associations with anaemia and OWOB were not consistently observed across model specifications. Policies should prioritise equitable access to affordable, nutrient-dense complementary foods, particularly in sub-Saharan Africa and socioeconomically disadvantaged populations.