New findings conclude U.S. children may lack healthy level of vitamin D

BOSTON As many as 20% of children in the United States between the ages of 1 and 11 years may suffer from suboptimal levels of vitamin D, according to a large nationally representative study published in the November issue of Pediatrics, Children’s Hospital Boston announced Monday.

The study, led by Jonathan Mansbach of Children’s Hospital Boston, is the most up-to-date analysis of vitamin D levels in U.S. children. It builds on the growing evidence that levels have fallen below what’s considered healthy, and that black and Hispanic children are at particularly high risk.

Both the optimal amount of vitamin D supplementation and the healthy blood level of vitamin D are under heated debate in the medical community, the hospital suggested. Mansbach and collaborators from the University of Colorado Denver and Massachusetts General Hospital used data from the National Health and Nutrition Examination Survey to look at vitamin D levels in a nationally representative sample of roughly 5,000 children from 2001-2006. Extrapolating to the entire U.S. population, their analysis suggests that roughly 20% of all children fell below the recommended 50 nmol/L. Moreover, more than two-thirds of all children had vitamin D levels below 75 nmol/L, including 80% of Hispanic children and 92% of non-Hispanic black children.

“If 75 nmol/L or higher is eventually demonstrated to be the healthy normal level of vitamin D, then there is much more vitamin D deficiency in the U.S. than people realize,” Mansbach said.

In the study, children taking multi-vitamins that included vitamin D had higher levels overall, but this accounted for less than half of all children. Mansbach recommended that all children take vitamin D supplements, especially those living in high latitudes, where the sun is scarce in the wintertime.

“We need to perform randomized controlled trials to understand if vitamin D actually improves these wide-ranging health outcomes,” Mansbach said. “At present, however, there are a lot of studies demonstrating associations between low levels of vitamin D and poor health. Therefore, we believe many U.S. children would likely benefit from more vitamin D.”