Vitamin d deficiency and its associated diseases: a concise review

Vitamin D is a fat-soluble vitamin that act as a hormone precursor that regulates calcium absorption and, in conjunction with the parathyroid hormone, bone mineralization. Vitamin D insufficiency leads to reduced bone mass, which can be manifested as the debilitating diseases of osteoporosis and osteomalacia in adults and rickets in children. Vitamin D deficiency is defined as 25-hydroxy vitamin D serum concentrations below 30 ng/ml. In this review article we tried to shed some light on how vitamin D is synthesized in human body and how vitamin D has connection with not just skeletal diseases but with various autoimmune diseases, metabolic disorders, neurological disorders.