AIM: To assess prevalence and population estimates of increased risk of 25-hydroxyvitamin D [25(OH)D] deficiency and inadequacy in US children based on the current Institute of Medicine Committee to Review Dietary References Intakes for Vitamin D and Calcium guidelines.

METHODS: The analysis was limited to a nationally representative sample of non-institutionalized US children and adolescents aged 6-18 years who participated in the National Health and Nutrition Examination Survey completed in 2003-2006 and had complete data on 25(OH)D measurements (n=2877). The 25(OH)D levels were adjusted for assay drift and prevalence, and population estimates of increased risk of 25(OH)D deficiency (/mL), risk of inadequacy (/mL), and adequacy (>20 ng/mL) were calculated.

RESULTS: Overall, 4.61% of children and adolescents are at increased risk of deficiency (population estimate 2.5 million) and 10.3% are at risk of inadequacy (population estimate 5.5 million) based on the Institute of Medicine guidelines.

CONCLUSION: Approximately 10.3% of US children aged 6-18 years (population estimate 5.5 million) have 25(OH)D levels/mL.