Usual Nutrient Intake Adequacy and Nutritional Status of United States Children and Adolescents: National Health and Nutrition Examination Survey 2001–March 2020

BACKGROUND: Comprehensive estimates of usual nutrient intake, supplement use, and nutrition-related biomarkers are lacking among children and adolescents. OBJECTIVES: The purpose of this secondary analysis of the United States National Health and Nutrition Examination Survey (NHANES) was to evaluate usual nutrient intake and nutrition-related biomarkers among individuals aged 1-18 y. METHODS: Individuals aged 1-18 y with ≥1 reliable dietary recall who participated in NHANES 2001-March 2020 were included for analysis. Pregnant females were excluded. Dietary intake was collected using 24-h dietary recalls administered via the Automated Multiple Pass Method, and supplement use was assessed from the 30 d supplement use questionnaire. Nutrition-related biomarkers were assessed from available cycles. Usual macronutrient and micronutrient intake was assessed using the National Cancer Institute method. Trends in usual intake across age groups were assessed using linear models. Differences between groups were assessed using independent samples t tests. All analyses were adjusted to account for the survey design and sampling weights. RESULTS: This representative sample of 32,118 individuals aged 1-18 y reported inadequate intake of key nutrients including dietary fiber, eicosapentaenoic acid, docosahexaenoic acid, vitamin D, and vitamin E. Inadequate calcium, magnesium, phosphorus, potassium, and vitamin A intake became increasingly common with age, particularly among adolescent girls, with mean (SE) 78.2 (1.3)% of girls aged 9-18 y reporting inadequate calcium intake. Younger children reported adequate iron and folate intake; however, 29.9 (1.3)% of adolescent girls had serum ferritin concentrations indicating iron deficiency, and 19.7 (1.2)% had red blood cell folate concentrations below recommended thresholds. Vitamin D insufficiency (serum 25-hydroxyvitamin D <50 nmol/L) also increased with age, affecting nearly 1 in 5 adolescent girls aged 9-18 y. Urinary iodine concentration of 20-100 μg/L was prevalent among all ages and gender groups. CONCLUSIONS: Micronutrient intake remained relatively stable across age groups despite increases in needs which was reflected by large proportions of those aged 9-18 y who reported inadequate intakes for vitamin D, vitamin E, calcium, magnesium, and iron.