Vitamin D deficiency

Vitamin D deficiency is due to low sun exposure (the skin can be converted to effective vitamin D after the skin is exposed to ultraviolet rays), insufficient intake (milk, egg, liver, fish, etc.) Absorption disorders (small bowel disease) and increased demand (pediatrics, pregnant women, nursing mothers) and other factors make the systemic calcium and phosphorus metabolism disorders and bone changes caused by insufficient vitamin D in the body. Its prominent manifestations are rickets in children and osteomalacia in adults, and coexist osteoporosis. It also affects the functions of tissues and organs such as nerves, muscles, hematopoiesis, and immunity, and seriously affects children. Growth and development.