A new study led by researchers at the University of Copenhagen has confirmed that vitamin D plays an important role in activating immune defenses against infectious diseases like flu.
Vitamin D deficiency has already been linked to a wide spectrum of diseases including heart disease, cancer, diabetes, depression, autoimmune disease and many others.
The study published in the latest edition of Nature Immunology discovers that activation of T-cells to fight infections needs definite help from vitamin D.
Carsten Geisler and colleagues, study authors, explained the role vitamin D plays in the immune responses as follows.
First when the naive T cell recognizes foreign invaders like bacteria or viruses with T cell receptor (TCR), it sends activating signals (1) to the vitamin D receptor gene. The VDR gene then starts producing DVR protein, which binds vitamin D in the T cell (3) and becomes activated. Then the vitamin D bound and activated DVR gets into the cell nucleus and activates the gene for PLC-gamma1 (5), which in turn produces PLC-gamma1 protein (6) and “the T cells can get started”.
In the case of flu fighting, Dr. John Cannell and his colleagues have reported that vitamin D helps produce antibacterial peptides that help protect against flu. That is why in winter people are prone to becoming vitamin D deficiency and getting infected with flu viruses.
Dr. Cannell, a vitamin D expert and director of Vitamin D Council, says in his newsletter sent last year that two physicians, one in Wisconsin and the other in Georgia reported to him that few of their patients/residents who maintained a high level of serum vitamin d acquired swine flu last year while many of other patients and medical workers who did not take vitamin D to maintain high vitamin D levels got swine flu and other flu viruses.
By David Liu /Credit: Professor of Immunology, Carsten Geisler