by Don Pearson, Technical Director BioBrew Ltd
Maintaining an intact intestinal barrier is fundamental for a healthy relationship with the gut microbiome. A healthy, properly functioning, intestinal barrier will keep pathogens and harmful microbial products away from our body. It will also keep out “good” microbes and many large allergenic molecules.
At the same time the intestinal epithelium needs to be selectively permeable to microbial signalling molecules as well as the metabolites that contribute to the health of our gut and immune system.
A breakdown in the function of the intestinal barrier can alter its permeability and lead to what is commonly known as “leaky gut.” Leaky gut is fundamentally about two things:
(1) large, often allergenic molecules, e.g., gluten, being allowed to pass through intact cell membranes due to changes in the transport mechanisms and
(2) loosening of the tight junctions between epithelial cells.
This leads to the intestinal barrier becoming permeable to things to things we don’t want to get in.
These changes in the permeability of the intestinal barrier compromises our ability to block the access of microbes and large allergenic molecules to our body. This results in chronic inflammation and altered immune responses that can in turn alter the composition gut microbiome and set up an feedback loop that is destructive to the host (Camilleri, 2019). Fortunately, dietary factors can reverse the leakiness and damage to the surface of the epithelium cells. Particularly low allergenic fermented foods (Camilleri, 2019).
Leaky gut can show up as a variety of signs and symptoms, which have in common aspects of chronic inflammation and immune system issues (e.g., autoimmunity, allergies).
- Camilleri, (2019). Leaky gut: mechanisms, measurement and clinical implications in humans. Gut volume 68, issue 8