D helps to maintain and promote our gut barrier D works by increasing specific proteins that are needed to maintain tight gap junctions which are like the glue that holds our gastric skin (epithelial) cells together, if our gap junctions are loose it can cause food intolerance read more about it here https://samanthah22.sg-host.com/blog/gut-function-and-food-intolerance-how-healing-the-gut-can-reduce-food-intolerance
D also has anti-inflammatory properties which keep the wall of the gut lumen tight- inflammation is heavily linked to food intolerance which you can read more about in the link above.
The link between D deficiency and Food intolerance is still in contention, However most of the evidence supports the link between D deficiency and food intolerance.
While the evidence is not well documented let me show you how D functions and draw a picture of how this vitamin may be indicated in food intolerance.
Firstly let me say D excess and deficiency in pregnancy have both been linked to food allergy in infants.
however an excess of D is over 5000Iu, most supplements have a dosage of 1000Iu; so you’d have to dose your self 5 times per day to get to that amount.
Vitamin D’s impact on the immune system: D works by regulating the immune system. It balances the immune function so it doesn’t over react to the chemicals in food.
Our Immune function has T cells B cells and natural killer cells. In food allergy we are concerned with T cells and B cells. T cells have 2 helper T functions Th1 and Th2 cellular response cells. If either of these functions become over reactive we can see diseases develop such as in
Food intolerance is often characterized as a Th2 response which is why if you are deficient in D the immune modulating functions that we rely on may not work and can lead to these conditions.
A substance called IgE which is a product of our natural immune function can be over active in food intolerance. IgE is an antibody produced by our immune system in response to a perceived threat, unfortunately in food intolerance our body perceives the food as a threat and creates IgE antibodies to combat the threat which causes inflammation, swelling and often pain, this can cause IgE hypersensitivity, meaning we react quicker and stronger to this antibody.
D regulates IgE hypersensitivity and supplementation of D has shown to down regulate hypersensitivity.
This is free article and a great read
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4555110/
I f you are suffering from food intolerance and need expert advice contact a naturopath or nutritional consultant.