Dietary diversity moderates household economic inequalities in the double burden of malnutrition in Tanzania

Objective: Improved food availability and a growing economy in Tanzania may insufficiently decrease pre-existing nutritional deficiencies and simultaneously increase overweight within the same individual, household or population, causing a double burden of malnutrition (DBM). We investigated economic inequalities in DBM at the household level, expressed as a stunted child with a mother with overweight/obesity, and the moderating role of dietary diversity in these inequalities. Design: We used cross-sectional data from the 2015-2016 Tanzania Demographic and Health Survey. Setting: A nationally representative survey. Participants: Totally, 2867 children (aged 6-23 months) and their mothers (aged 15-49 years). The mother-child pairs were categorised into two groups based on dietary diversity score: achieving and not achieving minimum dietary diversity. Results: The prevalence of DBM was 5<middle dot>6 % (s d = 0<middle dot>6) and significantly varied by region (ranging from 0<middle dot>6 % to 12<middle dot>2 %). Significant interaction was observed between dietary diversity and household wealth index (P-for interaction < 0<middle dot>001). The prevalence of DBM monotonically increased with greater household wealth among mother-child pairs who did not achieve minimum dietary diversity (P-for trend < 0<middle dot>001; however, this association was attenuated in those who achieved minimum dietary diversity (P-for trend = 0<middle dot>16), particularly for the richest households (P = 0<middle dot>44). Analysing household wealth index score as a continuous variable yielded similar results (OR (95 % CI): 2<middle dot>10 (1<middle dot>36, 3<middle dot>25) for non-achievers of minimum dietary diversity, 1<middle dot>38 (0<middle dot>76, 2<middle dot>54) for achievers). Conclusions: Greater household wealth was associated with higher odds of DBM in Tanzania; however, the negative impact of household economic status on DBM was mitigated by minimum dietary diversity.