Self-reliance in advanced diagnostic imaging for accessible, affordable, and quality health care in India

Abstract

The role of Vitamin D in regulating physiological calcium dynamics is well known in relation to bone metabolism. Hence, physiological concentration of Vitamin D is essential for optimal bone health. The optimal concentration of Vitamin D can be maintained by exposing the skin to adequate amount of sunlight or by taking Vitamin D supplement. However, in regions devoid of adequate sunlight, taking Vitamin D supplement is the only option. Unfortunately, the risk– benefit analysis of Vitamin D supplement is still unclear. While some studies have reported the benefits of Vitamin D supplementation, many others have contradicted this claim. A few studies have also reported harmful effects from excessive Vitamin D supplementation. Despite this lack of clarity, the Vitamin D supplement market is projected to be worth Euro 1.5 billion by 2025 with a compound annual growth rate of 12.5%. The strong growth projected in the Vitamin D market is attributed to increasing prevalence of Vitamin D deficiency globally, including geographical regions with adequate sunshine. While the reasons for the increased prevalence of Vitamin D deficiency are not clear, the association of Vitamin D deficiency has been reported with disease conditions beyond bone health. Such an association of Vitamin D deficiency with several disease conditions is not surprising, considering its influence on calcium dynamics, as there is hardly any physiological event which is independent of calcium involvement. Several recent studies have associated Vitamin D deficiency with vascular inflammation and endothelial dysfunction, which remain a hallmark of several disease pathophysiology including cardiovascular diseases. Vitamin D by increasing the activity of sphingomyelinases enhances the clearance of low‐density lipoprotein (LDL) and very LDL and hence reduces inflammation and macrophage adherence, potentially reducing cardiovascular disease risk. Vitamin D is also reported to improve vascular health in chronic kidney disease patients by upregulating thrombomodulin levels. Indeed, the role of Vitamin D as a vascular protective factor is promising and should be further explored. Included in this issue is a study reporting the association of Vitamin D deficiency with inflammatory marker such as high sensitivity C‐reactive protein and disease duration in a cohort of patients with diabetes. Based on its results, the study recommends regular screening of patients with diabetes for their Vitamin D levels as a potential risk analysis of their vascular health. While the evidence for Vitamin D deficiency is valid and reliable, the question remains in the interim, should we overcome Vitamin D deficiency naturally by exposing to sunlight or take the supplements?