Vitamin D deficiency in children: A review on prevention and treatment strategy.

As an essential fat-soluble vitamin in human body, the main function of vitamin D (VD) is mediated by its receptor. In the past decade, VD has drawn gradual and consistent attention from the scientific community and health professionals. According to epidemiological survey, approximately one billion people are under the state of vitamin D insufficiency or deficiency in the world. This phenomenon is also very common in China. By participating in calcium and phosphorus absorption from GIT, VD stands as a very important functional immune regulator. It plays a vital role in modulating both innate and adaptive immune responses, mainly through the modulation of growth, differentiation and function of a variety of immune cells, and the influence of secretion of cytokines and antimicrobial peptides. VD deficiency and pediatric diseases such as acute lower respiratory infection and asthma are associated with not only pediatric skeletal disorders (including nutritional rickets，osteomalacla，and osteoporosis), but also pediatric non-skeletal disorders, such as mortality rate, cardiovascular disorders and mortality，metabolic syndrome (including obesity，impaired glucose tolerance (IGT), diabetes mellitus, lipid metabolism disorders and hypertension), cancer，infection，allergy and asthma, neurological and mental diseas-es，autoimmune diseases，and chronic kidney diseases. Although VD treatment of skeletal disorders has been widely recognized，its efficacy and long-term effect on non-skeletal disorders is not clear. Hence, for the benefit of general children and their families, aim of the present review is to determine some convincing facts of evidence-based medicine about Chinese children, and to discuss certain reasonable, right and effective measures to prevent VD deficiency thereby reducing the risk of rickets.