Half of Black Teens May Be Vitamin D Deficient

Mar. 5 -- WEDNESDAY, March 4 (HealthDay News) -- Many teens today, especially black teens, aren't getting enough of vitamin D, the so-called sunshine vitamin that is essential for cells to function, say researchers from Weill Cornell Medical College in New York City.

Vitamin D deficiency has been linked to many chronic diseases, including heart disease, diabetes, immune system problems and inflammatory diseases.

"There is evidence that the levels of vitamin D we have been using in the past may have been too low," said lead researcher Dr. Sandy Saintonge, a fellow in general preventive medicine at Weill Cornell.

Vitamin D is measured by blood levels of 25-hydroxyvitamin D. Currently, people whose vitamin D level is less than 11 nanograms per milliliter (ng/mL) are classified as deficient, but many experts believe that the minimum level of vitamin D should be at least 20 ng/mL.

Several factors can interfere with the amount of vitamin D the body produces, including diet, sun exposure, use of sunscreen and skin color. Blacks take in less of the sun's rays than whites, causing less vitamin D production, Saintonge noted.

The report was published in the March 3 issue of Pediatrics.

For the study, Saintonge and her colleagues collected data on 2,955 youths, 12 to 19 years old, who participated in the National Health and Nutrition Examination Survey III. The researchers looked specifically at their levels of vitamin D.

Using the latest recommended level of vitamin D, the researchers found that, overall, 14 percent of adolescents in the study were vitamin D deficient. However, black teens were 20 times more likely to be vitamin D deficient than white teens.

Vitamin D deficiency among girls was more than double that of boys. In addition, twice as many obese teens were vitamin D deficient as normal-weight teens, Saintonge said.

She noted that more recent data puts the prevalence of vitamin D deficiency among teens at 40 percent to 50 percent.

Skin color, the prevalence of obesity and diet among black teens combine to make them more likely to be vitamin D deficient, Saintonge said. "It's a multi-factorial problem," she said.