| Vitamin D deficiency, as a disease with high morbidity in the population, has attracted more and more attention. The main diagnostic index of vitamin D deficiency is serum 25-hydroxyvitamin D level. Numerous studies have shown that vitamin D deficiency not only causes skeletal system diseases such as calcium and phosphorus metabolic disorders, rickets, osteomalacia, and osteoporotic fractures, but also causes cancer, immune system diseases, cardiovascular diseases, metabolic diseases (type 2 diabetes mellitus and obesity), muscle dysfunction, falls, and other extraskeletal system diseases. The effect of vitamin D deficiency on the skeletal system has been widely recognized in the academic circles. However, the effect of vitamin D deficiency on the extraskeletal system is still controversial in the academic circles. In this review, the research progress of vitamin D deficiency on skeletal and extraskeletal effects is comprehensively introduced, and the possible mechanism of vitamin D is discussed. The exploration of the effect of vitamin D deficiency on skeletal and extraskeletal system not only provides new research ideas for studying the possible mechanisms of vitamin D deficiency on skeletal and extraskeletal system, but also provides new clinical ideas for preventing and treating diseases related to vitamin D deficiency. Although there are different opinions on the extraskeletal effects of vitamin D deficiency, there is ample evidence that adequate vitamin D supplementation contributes to good health. |