Vitamin D is essential for bone health. Bone growth is high during childhood and adolescence. So it may be especially important to identify and treat vitamin D deficiency during that time, the researchers write.
Researchers in the study analyzed data from more than 12,000 U.S. children and teens aged 6 to 18. The children were enrolled in the 2003-2006 National Health and Nutrition Examination Survey.
About 21% of the healthy-weight youngsters were deficient in vitamin D. That was also true for 29% of those who were overweight, 34% of those who were obese, and 49% of those who were severely obese.
Even after accounting for such factors as vitamin D supplementation and intake of milk, which is typically fortified with vitamin D, the rates of vitamin D deficiency were higher in Latinos and African-Americans. Among the severely obese youngsters, 27% of whites, 52% of Latinos, and 87% of African-Americans were deficient in vitamin D.
"The particularly high prevalence in severely obese and minority children suggests that targeted screening and treatment guidance is needed," the researchers conclude.
Researcher Christy Turer, MD, a pediatrician at the University of Texas Southwestern Medical Center and Children's Medical Center in Dallas, says she and her colleagues already were routinely checking vitamin D levels in children at specialty clinics, such as weight management clinics. Those found to be deficient are prescribed high-dose vitamin D supplements, a pill taken weekly. After eight weeks of treatment, their levels are rechecked, and if they're near normal, she'll cut them back to monthly doses of vitamin D supplements.
Turer also recommends that vitamin-D-deficient patients drink low-fat milk. If they don't like to drink plain milk, she says they can add artificially sweetened flavors that add only 15 calories a serving.
"The reason that milk is important is it has not just vitamin D, but it has calcium," she says. Unsweetened soy milk and almond milk are also good sources of vitamin D and calcium, Turer says.