Seven out of ten U.S. children low in vitamin D

Seven out of ten U.S. children have low levels of vitamin D, raising their risk of bone and heart disease, according to a study by researchers at Albert Einstein College of Medicine of Yeshiva University. The striking findings suggest that vitamin D deficiency could place millions of children at risk for high blood pressure and other risk factors for heart disease.

The study, "Prevalence and Associations of 25-Hydroxyvitamin D Deficiency in Children and Adolescents in the United States: Results from NHANES 2001-2004," was published today in the online edition of Pediatrics.

"Several small studies had found a high prevalence of vitamin D deficiency in specific populations, but no one had examined this issue nationwide," says study leader Michal L. Melamed, M.D., assistant professor of medicine and of epidemiology & population health at Einstein. Dr. Melamed has published extensively on the importance of vitamin D.

The researchers analyzed data on more than 6,000 children, ages one to 21, collected by the National Health and Nutrition Examination Survey (NHANES) 2001-2004. They found that 9 percent of the study sample, equivalent to 7.6 million children across the U.S., was vitamin D deficient (defined as less than 15 ng/mL of blood), while another 61 percent, or 50.8 million, was vitamin D insufficient (15 to 29 ng/mL). Low vitamin D levels were especially common in children who were older, female, African-American, Mexican-American, obese, drank milk less than once a week, or spent more than four hours a day watching TV, playing videogames, or using computers.

The researchers also found that low levels of vitamin D deficiency were associated with poor bone health, higher systolic blood pressure, and lower calcium levels and HDL (good) cholesterol levels, which are key risk factors for heart disease.

"We expected the prevalence of vitamin D deficiency would be high, but the magnitude of the problem nationwide was shocking," says lead author Juhi Kumar, M.D., M.P.H., a fellow in pediatrics at Children's Hospital at Montefiore Medical Center, The University Hospital and Academic Medical Center for Albert Einstein College of Medicine.

The authors recommend that pediatricians should routinely screen high-risk children for vitamin D deficiency, and that parents should ensure that their kids get adequate amounts of the vitamin through a combination of diet, supplements, and exposure to sunlight.

As for parents, says Dr. Melamed, "It would good for them to turn off the TV and send their kids outside. Just 15 to 20 minutes a day should be enough. And unless they burn easily, don't put sunscreen on them until they've been out in the sun for 10 minutes, so they get the good stuff but not sun damage."

Albert Einstein College of Medicine of Yeshiva University is one of the nation's premier centers for research, medical education and clinical investigation. It is home to 2,775 faculty members who received more than $130 million in support from the NIH for major research in 2008.