The news today that some 40 percent of infants and toddlers have vitamin D deficiency should make parents listen up and take action. Vitamin D is vital for healthy bone development, and breast-fed babies don't get enough from their mother's milk. They also aren't producing enough from sunlight—the best source of vitamin D; pediatricians currently advise parents not to take kids into the sunny outdoors without first applying sunscreen or putting up the hood on the stroller.
The study published in today's Archives of Pediatrics and Adolescent Medicine found that babies who were breast-fed without getting a vitamin D liquid supplement were a whopping 10 times more likely to have vitamin D deficiency than those who were formula fed. (Formula, like cow's milk, is fortified with vitamin D.) But even bottle-fed infants and milk-drinking toddlers had unacceptably low levels of the vitamin. That could be detrimental not just for their bones but also to protect against "asthma, cancer, cardiovascular disease, diabetes mellitus, depression and schizophrenia," writes James Taylor, a professor of pediatrics at the University of Washington, in an editorial that accompanied the study; he concludes, "vitamin D deficiency may be a more serious problem in children than in adults."