Background Although vitamin D deficiency has been documented as a frequent problem in
studies of young adults, elderly persons, and children in other countries, there are limited
data on the prevalence of this nutritional deficiency among healthy US teenagers. Objective
To determine the prevalence of vitamin D deficiency in healthy adolescents presenting for
primary care. Design A cross-sectional clinic-based sample. Setting An urban hospital in
Boston. Participants Three hundred seven adolescents recruited at an annual physical …