Study Finds Many Children Have Low Levels of Vitamin D, Black Children More Likely To Be Affected
Of children living in the Northeast U.S., 55% had low levels of vitamin D and more than 90% of black children had low levels, according to a study in the American Journal of Clinical Nutrition, Bloomberg reports. For the study, Babette Zemel, director of the Nutrition and Growth Laboratory at the Children's Hospital of Philadelphia, and colleagues measured a biomarker for vitamin D in the blood of 382 children ages six to 21 who live in the Northeast. They also examined children's consumption of vitamin D from food and supplements.
Vitamin D deficiency can lead to poor absorption of bone minerals and can contribute to cancer, multiple sclerosis, hypertension and diabetes, researchers said. Diets low in vitamin D have been associated with allergies to dairy, lactose intolerance and strict vegetarian diets. More than 80% of blacks, American Indians and Asian-Americans are lactose intolerant. Fortified milk is the primary source of vitamin D in diets, while sun exposure is considered the best way to increase levels of the vitamin. The study did not look at vitamin D levels related to sunlight exposure.
Sixty-eight percent of children had low vitamin D levels during the winter months, when they received less sun exposure, the study found. Children older than age nine, those who did not consume enough vitamin D in their diets and blacks were more at risk of low vitamin D levels. Researchers also found that children with low levels of vitamin D were more likely to be from low-income households, have undereducated caregivers and be overweight.
Zemel said, "Vitamin D deficiency remains an under-recognized problem overall, and is not well studied in children." Researchers said that further research should examine the effect of sun exposure on vitamin D levels and should look at children in multiple test sites (Bloomberg, 7/9).
An abstract of study is available online.