Vitamin D Supplementation Slashes Risk of Respiratory Infection in Children

New research suggests that a daily dose of vitamin D may help to reduce the risk of acquiring respiratory infections over winter. Carlos Camargo, MD, a professor of Medicine at Harvard Medical School, and colleagues studied 247 Mongolian schoolchildren who were deficient in vitamin D. The children were randomly assigned to drink milk fortified with 300 IU of vitamin D3 or unfortified regular milk (control) between January and March. By the end of the study, average vitamin D levels had risen significantly in children receiving the fortified milk, from 7ng/mL at baseline to 19 ng/mL, but had remained at 7 ng/mL in the control group. Results showed that the children receiving vitamin D experienced approximately half the number of respiratory infections than children in the control group. "Our randomized controlled trial shows that vitamin D has important effects on infection risk," said Professor Carmargo. "In almost 250 children with low blood levels of vitamin D during winter, we found that taking a daily vitamin D supplement cut in half the risk of a respiratory infection." The authors note that low baseline vitamin D levels similar to those in the study participants are relatively common in some groups of Americans, particularly African-American children living in northern states.