Vitamin D deficiency and its health consequences

Abstract

Vitamin D is a group of liposoluble components that organisms can obtain either via endogenous production from sun exposure or directly taken from foods and dietary supplements. In addition to its involvement in calcium metabolism, its presence plays other important functions in human health (e.g. reduction of inflammation and effects on cell proliferation and differentiation). The discovery that most tissues and cells in the body have a vitamin D receptor and that several possess the enzymatic machinery to convert the primary circulating form of vitamin D (25-hydroxycholecalciferol, hydroxylated vitamin D3) to the active form (1,25-dihydroxycholecalciferol, calcitriol) has provided new insights into the function of this vitamin. Of great interest is the role it can play in decreasing the risk of many chronic illnesses, including common autoimmune diseases, cardiovascular disease, and cancers among others. This chapter reviews the nature of vitamin D deficiency, its causes and effects on the human organism, and suggest strategies for its prevention and treatment by both natural sources and/or vitamin D supplements.© 2010 Nova Science Publishers, Inc. All rights reserved.