Use of Vitamin D in Children and Adults: Frequently Asked Questions

In recent years, the increase in interest and use of vitamin D has been attributed mainly to the extra-skeletal effects of vitamin D and confusion about normal reference values for serum 25-hydroxy vitamin D (25-OHD). However, The Institute of Medicine, which determines daily intake of nutrients, vitamins and minerals in the United States, emphasizes that there is no additional benefit of having a 25-OHD level above 20 ng/mL in terms of parathyroid hormone suppression, calcium absorption and “fall risk”. Taking into consideration that there has not been a significant increase in vitamin D deficiency and related conditions in Turkey over the past five years, it is not hard to suppose that this increased interest is due to doctors, using mass media platforms, who have made claims that vitamin D is a “panacea”. This paper aims to answer some frequently asked questions such as the threshold values recommended for the evaluation of vitamin D status, the clinical indications for measuring 25-OHD and suggestions on the use of lifelong vitamin D starting from pregnancy.