After years of hectoring new parents about the need to keep babies protected from the sun's fierce ultraviolet rays, doctors may be about to swing back the other way. A new study shows that many infants and toddlers aren't getting enough Vitamin D, which is produced in human skin during exposure to sunshine. Vitamin D is essential for bone growth and absorption of calcium in the digestive tract, and also plays a role in regulating the immune system. But doctors disagree on the severity of the problem posed by the low vitamin D levels found in the study, and are also divided on what course of action to recommend. In the study, which appeared in the Archives of Pediatrics & Adolescent Medicine, researchers took blood samples from children ranging in age from 8 to 24 months, and found that 40 percent had below-optimal levels of the nutrient, while 12 percent were actually vitamin D deficient. The findings ... also showed that one-third of children who were deficient had changes in bone density seen on X-rays of the wrist and knee. A few even had signs of rickets, or softening of the bones caused by severe deficiency of vitamin D.
"We didn't pick up a lot of rickets, but we did pick up a lot of vitamin D deficiency," said Dr. Catherine Gordon, director of the Bone Health Program at Children's Hospital Boston and one of the study's co-authors. "We need to be concerned" [ABC News].
Vitamin D does not naturally occur in many foods, but milk, baby formula, and breads are often fortified with it. Because breast milk is known to lack the vitamin, pediatricians often prescribe vitamin supplements to breast-fed babies, a practice that Gordon's study supported; the breast-fed babies in her research sample were more likely to have low levels of the vitamin. While this study seems to sound an alarm, another researcher cautioned against rushing to judgment. In an accompanying editorial, Dr. James Taylor wrote that the level of vitamin D that Gordon defined as below-optimal might not be a cause of concern, and that the changes she saw in some children's bones might not be dangerous.
"It might be that for many of the children with osteopenia [low bone density], the changes are transient and not indicative of disease. Time and more research will tell" [Archives of Pediatrics & Adolescent Medicine, subscription required].
Gordon advised that breast-feeding mothers give vitamin supplements to their babies, and also take some themselves -- in fact, all children can benefit from a daily multivitamin containing vitamin D, she said.
Taylor wasn't as convinced about the need for routine supplementation, however. "I think that more research is needed before routine vitamin D supplementation is recommended for all children," he said [The Washington Post].