The Double Burden of Malnutrition: A Systematic Review of Operational Definitions.

BACKGROUND: Despite increasing research on the double burden of malnutrition (DBM; i.e., coexisting over- and undernutrition), there is no global consensus on DBM definitions. OBJECTIVES: To identify published operational DBM definitions, measure their frequency of use, and discuss implications for future assessment. METHODS: Following a structured search of peer-reviewed articles with terms describing "overnutrition" [e.g., overweight/obesity (OW/OB)] and "undernutrition" (e.g., stunting, micronutrient deficiency), we screened 1920 abstracts, reviewed 500 full texts, and extracted 623 operational definitions from 239 eligible articles. RESULTS: We organized three identified DBM dimensions (level of assessment, target population, and forms of malnutrition) into a framework for building operational DBM definitions. Frequently occurring definitions included coexisting: 1) OW/OB and thinness, wasting, or underweight (n = 289 occurrences); 2) OW/OB and stunting (n = 161); 3) OW/OB and anemia (n = 74); and 4) OW/OB and micronutrient deficiency (n = 73). CONCLUSIONS: Existing DBM definitions vary widely. Putting structure to possible definitions may facilitate selection of fit-for-purpose indicators to meet public health priorities.