Vitamin D and Immune Health
Vitamin D is also a hormone that helps regulate the immune system.[2] Studies show vitamin D plays an important role in both the innate and adaptive immune systems.
Suggestions linking vitamin D and immune function in part originate from observations of disease occurrence based on geographic location. Vitamin D is primarily obtained through synthesis in the skin following sun exposure, and levels of UV light vary according to latitude (distance from the equator). Higher latitude is often an indicator of lower levels of UV exposure and lower vitamin D status. The incidence or prevalence of a disease increases with increasing distance from the equator.[3]
Innate and Adaptive Immune Systems
Research has shown vitamin D is involved in the innate and adaptive immune systems. Several cell types of the immune system, including T cells, B cells, neutrophils, and macrophages express the Vitamin D Receptor (VDR), symbolic of their capacity to be decreased by vitamin D signaling. Vitamin D is involved in antimicrobial activities of macrophages and monocytes[2,4] and antiviral activity against many respiratory viruses[5,6].
Vitamin D and its metabolites exert multiple phenotypic effects on the vascular endothelium via multiple pathways that are protective against vascular dysfunction and tissue injury[1]. Furthermore, multiple studies have shown that vitamin D plays a role in gut integrity and intestinal homeostasis between host and gut microbiota. Signaling vitamin D increases the viability of intestinal cells and eases intestinal damage from bacteria that activate the immune system.
Vitamin D’s role in the innate immune system has important clinical implications, made evident by the increase in vitamin D-deficient individuals resulting in the increased susceptibility to bacterial infection[1].
Read more “Importance of Vitamin D in Managing Your Immunity”