What is Quercetin?
Quercetin is a natural plant flavonoid found in red onions, capers, kale, and other common foods containing appreciable amounts of quercetin.
What does Quercetin Do?
Mast cells play a part in developing and maintaining leaky gut, as when these mast cells become unstable or degranulate, this causes histamine release.
Histamine is the chemical that causes allergy symptoms, but it can also cause and contribute to leaky gut.
By using quercetin as a mast cell stabilising agent, we can reduce/stop the degranulation and release of histamine and allow the gut lining the opportunity to repair itself.
But quercetin works in another important way for the gut…
Quercetin has also been shown to enhance gut barrier function by having a “sealing” effect due to its role in the assembly and expression of tight junction proteins: zonula occludens-1, occludin, junctional adhesion molecule-A, claudin-3.
By blocking mast cell degranulation, quercetin can also allow the Di-Amine Oxidase (DAO) enzyme to catch up to the backlog of excess histamine, and help reduce food sensitivities/reactions and reduce the burden on the immune system.
The bioavailability of quercetin in humans is low and highly variable (3-17%), and it is rapidly cleared with an elimination half-life of 1–2 hours after ingesting quercetin foods or supplements.
Quercetins main effect in this product is on the expression of tight junction proteins and stabilisation of mast cells in the lamina propria (the layer just behind the epithelial layer), therefore the low bioavailability and low circulating levels of this flavonol are not necessarily reflective of its efficacy for gut healing as its effects can remain local to the gut, and the absorption will also be dependant on ones barrier integrity; the ‘leakier the gut’ the more quercetin will pass to the lamina propria and the better the flavonol will lower permeability.
Quercetin significantly induces the gene expression as well as the production of Th-1 derived interferon-γ (IFN-γ) and down-regulates Th-2 derived interleukin 4 (IL-4) by normal peripheral blood mononuclear cells (PBMC)
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