Commentary: Identify and Treat Patients With Vitamin D Insufficiency

I also do not recommend bone density measurements (such as dual-energy x-ray absorptiometry, or DXA) because many of these scans can be misread. You want to take a history, get a vitamin D level, and treat. Otherwise, you are just going to run up medical expenses.

Ultraviolet light from sun exposure triggers a reaction that provides vitamin D. The necessary amount of sunshine for infants is about 30 minutes per week if they are wearing only diapers or 2 hours per week if fully clothed. That evidently provides an adequate amount of vitamin D. Of course, the concern about skin cancer leads us to recommend sunscreen for people who are outdoors for more than just a short period. If children and teenagers are really out in the summer, which is when most get exposure, they're putting on sunscreens that block about 95% of the rays. So we have become dependent on diet for our vitamin D, and we're not getting it.

Dr. Robert Schwartz is professor of pediatrics and chief of pediatric endocrinology at Wake Forest University in Winston-Salem, N.C. He said that he had no relevant financial disclosures.