Gut Flora and the Immune System
As well as including many inflammatory foods that contribute to leaky gut, the modern diet also contributes to autoimmune reactions and other immune problems in another way: it causes gut dysbiosis, or a disruption of the helpful gut flora that live in our intestines.
Gut flora are clearly linked to immune function and the prevention of leaky gut. Healthy gut flora support a functional intestinal barrier – they not only crowd out undesirable bacteria, but even actively help the gut destroy them. These friendly bacteria also help maintain the tight connections between the cells in the gut wall, shoring up the physical barrier to infection. On the other hand, disruption of the gut flora (especially bacterial overgrowth in the small intestine, abbreviated as SIBO) is linked to increased permeability. An overgrowth of bacteria in the small intestine actually causes the release of zonulin, the same chemical that regulates intestinal permeability in people with Celiac Disease who eat gluten. In other words, SIBO can provoke a Celiac-like leaky gut response even in people who don’t have Celiac disease or who aren’t eating any gluten.