Prevalence and determinants of vitamin D deficiency in infants and toddlers in the Netherlands: a pilot study

Background Little is known of the vitamin D status of young infants and toddlers and its determinants in West Europe. The prevalence and determinants of vitamin D deficiency of children aged 6-48 months in the centre of the Netherlands (52 degrees N) is investigated. Methods In a cross-sectional population study, randomly recruited infants and toddlers (n = 150) were studied using an online questionnaire and a physical examination either in late summer (n = 52) or in late winter (n = 98). Vitamin D analysis was performed by capillary blood sampling using dried bloodspots plus LC-MS/MS. Results In late winter, 32% of the children were vitamin D deficient (<50 nmol/L 25OH vitamin D3) with 5% severely deficient (<25 nmol/L). In late summer, 2% were deficient. The odds of vitamin D deficiency were higher in children aged 24-48 months, for those not using formula milk and those not adhering to the supplementation guidelines. Conclusion One-third of Dutch infants and toddlers were found to be vitamin D deficient in late winter. Suggested strategies for raising the vitamin D status may include improving the adherence to supplementation, a sensible sun exposure or the use of fortified foods. Special attention is needed for the children aged 24-48 months.