Dietary Diversity as a Measure of Nutritional Adequacy throughout Childhood

Malnutrition is a widespread concern in developing countries, impacting children's cognitive and physical development, quality of life and lifetime productivity. Interventions to improve nutritional status in international contexts require identification of at-risk populations and correct conclusions about general nutritional needs. Screening tools are currently being developed to meet these needs. Dietary diversity indicators are promising tools currently being studied. They are typically counts of food groups in the diet (i.e. a sum of defined food groups consumed in a defined time period) and are practical for field use because they are simply measured and positively correlated with nutrient intakes. We created age-specific diversity scores (based on a pre-existing tool) for use in both early childhood and adolescence, and evaluated their relationship to nutritional adequacy, nutritional status (measured by height for age Z-score), and their combined ability to predict adult height. Data were taken from the Cebu Longitudinal Health and Nutrition Survey, a Filipino birth cohort of 3,080 followed from the early 1980s through the present. We found that using minimum portion requirements improved the relationship of scores to nutrient adequacy for the 6 nutrients evaluated (vitamin A, iron, calcium, niacin, riboflavin, iron). Modified scores also reflected amounts of food consumed, i.e. children with increasing dietary diversity also ate larger amounts of individual food groups. Related increases in nutrient adequacy were largely due to these increased energy intakes, but there were also small increases in the nutrient density of the diet at both ages. Linear models were used to evaluate the relationship of both scores to height for age z-score. Scores at both ages predicted crude increases in height for age z-score, although this relationship was weaker for adolescents. After adjustment for confounders only the early childhood score was significantly related height for age z-score, and only when mother's had greater than 6 y of education. In the crude longitudinal model, combined score increases did not predict ultimate height improvements. This research provides important insights about how diversity scores may be improved for international malnutrition screening, and provides a basis for future research on the performance of diversity scores across childhood