Bone Health and the Physiologic Importance of Vitamin D

Abstract

Vitamin D plays a critical role in various physiologic processes throughout the body including
metabolism, immune support, and bone formation and mineralization. Vitamin D is chemically
modified by enzymatic reactions in the liver and kidney before it can be used by the rest of the
body. The process of how Vitamin D is absorbed and metabolically activated is important in
understanding how to diagnose and treat patients with low Vitamin D levels. While Vitamin D
toxicity can occur, Vitamin D deficiency is more common and can result in increased risk of
fractures in the elderly. Vitamin D deficiency can occur because of malabsorption, poor diet,
inadequate sun exposure and a variety of other causes. The purpose of this manuscript was to
explore the different functions of Vitamin D in the body and significant clinical effects if these
levels are below normal limits.