Vitamin D deficiency soars in the U.S., study says: Scientific American
Three-quarters of U.S. teens and adults are deficient in vitamin D, the so-called "sunshine vitamin" whose deficits are increasingly blamed for everything from cancer and heart disease to diabetes, according to new research.
The trend marks a dramatic increase in the amount of vitamin D deficiency in the U.S., according to findings set to be published tomorrow in the Archives of Internal Medicine. Between 1988 and 1994, 45 percent of 18,883 people (who were examined as part of the federal government's National Health and Nutrition Examination Survey) had 30 nanograms per milliliter or more of vitamin D, the blood level a growing number of doctors consider sufficient for overall health; a decade later, just 23 percent of 13,369 of those surveyed had at least that amount.
The slide was particularly striking among African Americans: just 3 percent of 3,149 blacks sampled in 2004 were found to have the recommended levels compared with 12 percent of 5,362 sampled two decades ago.
"We were anticipating that there would be some decline in overall vitamin D levels, but the magnitude of the decline in a relatively short time period was surprising," says study co-author Adit Ginde, an assistant professor at the University of Colorado Denver School of Medicine. Lack of vitamin D is linked to rickets (soft, weak bones) in children and thinning bones in the elderly, but scientists also believe it may play a role in heart disease, diabetes and cancer.
"We're just starting to scratch the surface of what the health effects of vitamin D are," Ginde tells ScientificAmerican.com. "There's reason to pay attention for sure."