| Vitamin D (VD) is an important vitamin that regulates bone metabolism. VD deficiency in infants and children can cause rickets, and VD deficiency in adults and the elderly can lead to osteoporosis. Recent studies have shown that VD is closely related to hypertension, type 2 diabetes mellitus, dyslipidemia, metabolic syndrome, allergic diseases and asthma, immune regulation and anti-inflammatory, anti-fibrosis, cardiovascular disease, tuberculosis, chronic kidney disease, various cancers, infections, and even death. With the advent of aging society and the improvement of modern living standards, people are paying more and more attention to the deficiency of VD, so there are fewer and fewer patients with VD deficiency. On the contrary, the cases of poisoning happen now and then caused by the overdose of VD. Safety should always be the primary consideration. When providing the human needs of VD in the range of toxic doses, adequate healthcare education on vitamin D intake level and vitamin D poisoning should be given. In addition to vitamin D supplementation, increasing outdoor activity time and more sun exposure could increase the endogenous production vitamin D. In the course of prevention and treatment of VD deficiency, we should pay attention to the dosage and timing of VD supplementation, give close observation and regular follow up to avoid the occurrence of VD poisoning, in order to reduce the incidence of vitamin D deficiency and the occurrence of vitamin D deficiency rickets. |