The tight junctions in your small intestine contain an adhesion junction around them to help regulate what gets in and what stays out. Dr. Tom O Bryan describes it like a “rubber band” wrapped around the tight junctions that can get too stretched out and lose its elasticity (ability to snap back in place).
Vitamin D plays a critical role in the elasticity of those rubber bands and how well they keep the tight junctions operating normally. Likewise, Vitamin D is an immune modulator, an essential steroid hormone that can promote balanced immunity.
Please read the article here
http://ajpgi.physiology.org/content/ajpgi/294/1/G208.full.pdf
