Vitamin D requirements of children: "all my life's a circle"

The importance of vitamin D for ensuring the health of children has long been understood. Over time, however, dietary recommendations for vitamin D intake have varied, with some eras seeing higher levels recommended and some lower. Remarkably, the current recommendations from the Institute of Medicine are not much different from those released with the first edition of the recommended dietary allowances in 1941. The present review examines the evolution of vitamin D recommendations over time and considers the differences and potential consequences related to the various recommendations in effect today. In considering strategies to evaluate the vitamin D status of children and efforts to assure its adequacy, individual caregivers and policy makers need to consider carefully the costs and potential risks of different screening strategies involving blood testing in children and of supplementation. More data on the long-term risks and benefits are needed before widespread screening or supplementation can be advocated.