Vitamin D Deficiency Is Not Associated with Growth or the Incidence of Common Morbidities among Tanzanian Infants

Document Type

Journal Article

Publication Date



Journal of Pediatric Gastroenterology and Nutrition








cohort studies; infant; micronutrients; nutrition; Vitamin D


© 2017 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition and the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition. Objective: The objective of this study was to examine risk factors for vitamin D deficiency and determine the association of vitamin D status with child growth and incidence of common morbidities among Tanzanian infants. Methods: A prospective cohort of 581 Tanzanian infants born to human immunodeficiency virus (HIV)-uninfected mothers had serum 25-hydroxyvitamin D assessed at 6 weeks and 6 months of age. Infants were seen at monthly clinic visits for growth monitoring until 18 months of age. Physicians examined infants every 3 months or when an illness was noted to document morbidities. Results: The prevalence of vitamin D deficiency (<20 ng/mL) declined from 76.4% at 6 weeks of age to 21.2% at 6 months. Infants who were exclusively breastfed at 6 weeks of age had 2.05 (95% confidence interval 1.11-3.79; P = 0.02) times the risk of vitamin D deficiency as compared formula-fed infants. After multivariate adjustment, there was no association of vitamin D status at 6 weeks or 6 months with the incidence of stunting, wasting, or underweight. There was also no association of low vitamin D with the incidence of diarrhea, upper respiratory infection, acute lower respiratory tract infection, or malaria. Conclusions: Vitamin D deficiency is common during early infancy, particularly among exclusively breastfed infants; however, these observational data suggest it may not be an important contributor to morbidity and growth among the general population of Tanzanian infants. Future studies of vitamin D among high-risk infants, including those with low birthweight and exposed to HIV, may be warranted.