Inadequate dietary intakes are a key underlying cause of undernutrition, which places children
at risk for impaired growth and development. Current estimates of prevalence of nutrient
inadequacies are needed for the design of interventions to improve child diet. Estimates of
nutrient intake variance components and validation of dietary diversity scores (DDS) among
children are needed to design studies of nutrient intakes or population-level dietary adequacy,
respectively. We conducted seven repeat 24-hour dietary recalls over six months among 4- to 8-
year-old rural Zambian children (n=202). Participating children were enrolled in the nonintervened
arm of a biofortified maize efficacy trial. We calculated observed nutrient intakes,
frequencies of food consumption, usual intakes over six months, usual intakes by survey round
and 7- and 10-food group DDS by survey round. Usual nutrient intakes over six months were
used to estimate the prevalence of inadequacy of eleven micronutrients. We estimated withinperson,
between-person and seasonal components of variance in observed nutrient intakes.
The performance of each DDS relative to overall nutrient intake adequacy and to usual intakes
of five selected micronutrients was assessed by season. Children’s diets were heavily plant
based and included few animal source foods. Estimated prevalence of inadequate calcium,
vitamin B12, folate and iron intakes was >99%, 76%, 57% and 25%, respectively. Mean nutrient
intakes differed significantly between three agricultural seasons and season accounted for 3%–
23% of total intake variance. Within- to between-person variance ratios were high due to low
between-person variance. DDS were associated with overall intake adequacy, but this
association was significantly weaker in the late lean season than in the late post-harvest or early
lean seasons. The heavily plant-based diet of rural Zambian children places them at risk for
inadequate nutrient intakes. Because nutrient intakes vary by season, future studies estimating
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usual intakes should include repeat observations in multiple seasons. The 10-food group DDS is
recommended over the 7-food group DDS for use as a population-level indicator of dietary
adequacy.