Department of Medicine, Cardiometabolic and Endocrine Institute, North Brunswick, NJ, USA
Review Article
Biology of Vitamin D
Author(s): Sunil Wimalawansa*
Vitamin D is both a vitamin and a hormone. It has pleotropic actions that extend beyond calcium and phosphate homeostasis, regulation of parathyroid hormone, and the prevention of osteomalacia, rickets, falls, and fractures. Over 80% of vitamin D requirement is expected to generate in the skin, following exposure to ultraviolet B in sunlight; globally, majority of people are however, under-exposed to sunlight. Nevertheless, over exposure to sunlight, does not cause hypervitaminosis D but can cause damage to skin cells. However, both extremes of vitamin D concentrations can be harmful. Vitamin D is essential for life, including for reproduction, fetal growth, and immunity, and proper functioning of body systems. Evidence supports wider beneficial effects of vitamin D but to achieve such, maintaining serum 25 dihydroxyvitamin D (25(OH)2D) concentrations of more than 30 ng/mL .. View More»
