Many healthy infants and toddlers are have low levels of vitamin D, according to a report released on June 2, 2008 in the Archives of Pediatrics and Adolescent Medicine, one of the JAMA/Archives journals. About one third of these children have some evidence of reduced bone mineral content on X-rays.
Several states in the US have recently reported a resurgence of vitamin D deficiency and in rickets, the resulting bone-weakening disease. The deficiency appears to be present in other countries as well, including Greece, China, Canada, and England.
To investigate the present state of the deficiency, Catherine M. Gordon, M.D., M.Sc., and colleagues at Children’s Hospital Boston, examined 380 children between the ages of 8 and 24 months who had visited a primary care center for physical examination between 2005 and 2007. Additionally, parents completed a questionnaire related to: the nutritional intake of themselves and their children, including vitamin D and other supplements; the amount of time spent outdoors; socioeconomic status; and level of education.
Blood samples were available for 365 of the children. Of these, 12.1% (44 children) had vitamin D deficiency, which was defined as 20 nanograms per milliliter of blood or less, while 40% (146 children) had vitamin D levels below the accepted level of 30 nanograms per milliliter.
In examining nutritional intake in these children, breastfed infants who received no vitamin D supplements were at a higher risk for deficiency, as were toddlers who drank less milk. Specifically, for each additional cup of milk toddlers drank each day, blood vitamin D level increased by 2.9 nanograms per milliliter.
Of the children with vitamin D deficiency, 40 underwent X-rays of the wrist and knee. In these observations, 32.5% (13 children) showed signs of bone mineral loss. Changes suggestive of rickets were seen in 7.5% (three children).
The authors summarized the results in relation to full rickets: “Only one child had signs of rickets on physical examination,” they state. “Thus, these infants and toddlers had a sub-clinical deficiency that could make detection of this issue particularly problematic in routine clinical practice, as a child’s vitamin D status is not typically evaluated as part of routine care.”
They further suggest that infants should received vitamin D supplements while breastfeeding. Additionally, they raise the issues of potential supplementation and regular blood measurement for children with established risk factors for vitamin D deficiency. “Given the potential benefits of vitamin D on bone and other tissues, and growing data supporting its immunomodulatory and antiproliferative effects, the current findings support recommendations advocating for vitamin D supplementation for all young children,” they say.
Prevalence of Vitamin D Deficiency Among Healthy Infants and Toddlers
Catherine M. Gordon, MD, MSc; Henry A. Feldman, PhD; Linda Sinclair, BA; Avery LeBoff Williams, BA; Paul K. Kleinman, MD; Jeannette Perez-Rossello, MD; Joanne E. Cox, MD
Arch Pediatr Adolesc Med. 2008;162[6]:505-512.
Written by Anna Sophia McKenney