Vitamin D Deficiency Among Healthy Infants and Toddlers: a Prospective Study from Irbid, Jordan

Background: The aim of this study was to estimate the prevalence of vitamin D deficiency among healthy infants and toddlers, as well as its associated factors, in Irbid, Jordan.

Methods: A total of 275 subjects (136 infants and 139 toddlers) aged 6-36 months participated in this study. Information concerning sociodemographic characteristics and early feeding patterns was collected using a self-guided questionnaire. Plasma vitamin D, calcium, phosphorous, and alkaline phosphatase activity were measured.

Results: The prevalence of vitamin D deficiency was 28% (16.7% for severe vitamin D deficiency and 11.3% for vitamin D deficiency) and vitamin D insufficiency was 28.4%. Plasma calcium and alkaline phosphatase levels showed no correlation with the vitamin D status of the study population. For both age groups, a significant association was found between vitamin D status and sun exposure (P < 0.001). A significant association between infant feeding practices and vitamin D status was found (P < 0.001). Infants who were exclusively breast-fed had higher risk for vitamin D deficiency and vitamin D insufficiency than those who were bottle-fed. Multivariate logistic regression analyses results showed that female sex, low sun exposure and exclusive breast-feeding were the main determinants of vitamin D levels.

Conclusion: The prevalence of vitamin D deficiency is considered to be high among northern Jordanian infants and toddlers. Sun exposure of less than 30 min daily and exclusively breast-feeding are the main factors for developing vitamin D deficiency.