I don’t come from a strictly medical background, and when anyone tries to explain what happens in the body through biological terms, my brain begins to clog up trying to remember the terms, instead of focusing on what is actually happening. Instead, I like to use similes, simple words (as best I can), and other methods to reach an understanding of how the body functions without the advanced college lecture.
Biological Breakdown (without the grueling terminology)
I like to think of the small intestine as a: paper tea strainer, nut milk bag, and cheesecloth. Except, imagine if these had little tentacles to reach out and grab nutrients while straining the good stuff into your body, and leaving the chunks and undesired particles in the bag (intestines).
The intestinal cells are structured into what’s known as tight junctions: they’re the gatekeepers that screen nutrients to decide what gets to enter the bloodstream, and what remains in the body to, ultimately, get pushed out. If these tight junctions become more permeable, meaning their lining is stretched out and opened, then they can’t function properly. It’s like playing red rover with a few inches between some hands, or only holding hands at the pinky: these gaps provide areas for food particles and toxins to slip into the bloodstream without a fight or screening.
Once particles slip into the bloodstream, they’re not safe if they don’t belong. The liver must work overtime, and cannot keep up, with trying to do the small intestine’s screening job. The immune system detects a problem, and rushes out to remove the perceived threat of a foreign particle (even if the particle is harmless). The immune system logs any data on a perceived threat, develops antibodies, and will battle anything that seems similar to the particle. Even healthy body cells are sometimes caught in battle, or in the crossfire of attack, from the immune system.
How does the cellular lining even expand so that particles escape into the bloodstream? The reasons vary from the cells being stretched apart, or the protective mucosal lining losing its barrier. The final result, though, is inflammation. Any irritant, such as NSAIDs, low stomach acid, fungal or bacterial overgrowth, parasites, toxins (such as breathing in unclean air), or excessive chemicals from eating habits can lead to inflammation. The cells cannot hold their tight junctions as they swell up.
Stress is another precursor, often taken for granted or avoided in conversation. Stress weakens the immune system both in and out of the gut. Pathogens are able to overpower the immune system, which once again, leads to inflammation.
Candida cells, aside from causing inflammation, can latch onto the cellular walls and stretch their own openings into the bloodstream.
Immune health begins at the gut. A 2008 analysis in Clinical & Experimental Immunology’s argued that up to 70% of immune health was in the gut, and around 80% was plasma cells. Dr. Alessio Fasano wrote a review in 2012 that covered the role of impaired intestinal barrier functions in autoimmune diseases. Probiotics help regulate immune function in the gut, and as a result, inflammation. When a probiotic or placebo was given to New Zealand rugby players, the group who took probiotics did not have any upper respiratory infections. Those on the placebo had to be treated more often for illness. The study was published in 2014 by the Journal of Science and Medicine in Sport.
Zinc is important for intestinal lining strength. Inflammatory Bowel Diseases published a study in 2001 demonstrating zinc’s ability to tighten the cells in patients with Crohn’s disease with 110mg of zinc sulfate taken three times daily.
Since Leaky Gut is not generally recognized in the medical field, there is no accurate test for it. However, the most common indication is a test of absorbancy. Two liquids, lactulose and mannitol, are drank. Depending on the results of which one(s) are better absorbed, intestinal permeability and malabsorption can be evaluated. If both liquids are elevated in the body, this signifies leaky gut. If mannitol is low, this signifies poor absorption of small molecules.
Each case of leaky gut is personal. Nutrients that trigger inflammation will vary per individual, and so designing a successful diet takes time and patience.