Vitamin D as a Neuroactive Substance: Review

The objectives of this paper were (1) to review recent research on the actions of vitamin D as a steroid derivative with neuroactive properties and (2) to highlight clinical relevance and need for more research. Our methods included review of research from current journals, Medline, and Cochrane Reviews; theoretical discussion. Scientific research has had a justifiably strong emphasis on how vitamin D affects calcium metabolism and bone. This appears to have eclipsed its fundamental actions on several other important systems, including the central nervous system. Vitamin D as a neuroactive compound, a prohormone, is highly active in regulating cell differentiation, proliferation, and peroxidation in a variety of structures, including the brain. Vitamin D insufficiency is not rare. Historically, focus has been on bone metabolism, which appears to have causedresearch biasandevidence bias, distorting physiological importance. The central nervous system is increasingly recognized as a target organ for vitamin D via its wide-ranging hormonal effects, including the induction of proteins such as nerve growth factor. We need more research on this important neuroactive substance because it may play a role as a relatively safe and inexpensive pharmaceutical in the prevention and treatment of a number of common neuropsychiatric conditions.