Ask Dr. Nick
On today’s episode, Dr. Nick talks about the connection between vitamin D and autoimmunity. Vitamin D is not actually a vitamin but a hormone!! Vitamin D3 can be obtained from food, but it is estimated that 80% is made in the skin from Ultraviolet B (UVB) light. Then, vitamin D3 uses two enzymes (one in the liver and other in the kidney) to become the hormone vitamin D or Calcitriol. Calcitriol has a variety of functions, but it is important in regulating the immune system. In the paper today, it was found that vitamin D (via UVB light or supplementation) modulates the gut microbiome by increasing its diversity. A diverse microbiome has been associated with improved health due to decreased gut and systemic inflammation. At the same time, presence of a leaky gut is a proposed requirement for development and relapse of autoimmunity. Therefore, proper vitamin D levels may improve the gut microbiome, decrease gut inflammation, and prevent autoimmune attacks. Check out the video for more in depth information on the effects of sunlight on the gut microbiome!
Reference: Bosman ES, Albert AY, Lui H, Dutz JP, Vallance BA. Skin Exposure to Narrow Band Ultraviolet (UVB) Light Modulates the Human Intestinal Microbiome. Front Microbiol. 2019;10:2410.