Leaky Gut Syndrome and Autoimmune Disease
At first glance, it may seem like a significant leap to accuse digestive dysfunction for being a culprit of immune dysregulation. However, the lining of our gastro-intestinal tract serves as an interface between our body and the external environment. Often, we consider the food we have eaten to have entered ‘inside’ of our body, but that is false. The food we eat only enters ‘inside’ our body once it has crossed the threshold of the epithelial lining of our digestive tract and been assimilated into the bloodstream. The digestive system therefore serves a very important defence and immune function, because it interacts with the outside world so frequently. There are numerous controls put in place to protect harmful substances from entering the bloodstream. One of which is the tight junctions of the cells that line the epithelium tissue of our gut. These tight junctions of cells regulate the permeability of our digestive tract, ensuring only molecules that are tiny enough to pass through the barrier can enter our bloodstream. Leaky Gut Syndrome, in a nutshell, is the loosening of these tight junctures and therefore increased permeability of the digestive lining. This allows larger molecules of food as well as microbes and other contaminants to enter the bloodstream. Our immune system recognizes these foreign microbes and molecules as potential pathogens, resulting in an immune response. This continuous activation of immune activity dysregulates the homeostasis of our immune system. Over time, chronic over-engagement of immunity may lead to auto-immune diseases, where the immune system attacks healthy tissues, causing damage and loss of function. Recent research suggests a link between leaky gut syndrome and the pathogenesis of autoimmune diseases such as Inflammatory Bowel Disease, Multiple Sclerosis, Rheumatoid arthritis and more.
The Gut Microbiome
Just like all mucosal tissue that interfaces with the outside world, our gut mucosa is home to trillions of microbial inhabitants that assist in the breakdown of our food, absorption of nutrients, protection from pathogens and immune function. This mucosal tissue is meant to protect the epithelial tissue underneath as well as trap pathogens. Disruption or absence of this mucosal layer exposes the underlying epithelial cells and causes inflammation and damage. Disturbances in the balance of the microbiome (dysbiosis) can disrupt the intestinal lining and loosen the tight junctures of the gastrointestinal lining. The microbiome is a competition between helpful and harmful microbes. The harmful microbes such as Candida sp., Salmonella sp., Giardia sp., Yersinia sp., Helicobacter pylori, Blastocystis hominids, Shigella sp., etc. excrete enterotoxins that injure the tight junctions of the GI tract. The presence of good bacteria in the gut protects us from colonization by bad bacteria. Additionally, studies show that the metabolites excreted by some good bacteria actually help protect the tight junctions of the gut. Unfortunately, chronic low-level exposure to antibiotics and pesticides in our tap water and food expose the microbiome to life-killing contaminants on a regular basis. This damages the microbiome and causes inflammation in the epithelial tissue. There is a great deal of research that supports the claim that glyphosate-based herbicides loosen the tight junctions of the gut, increasing intestinal permeability. The tight junctions in our gut are held together by protein complexes; studies show that glyphosate changes the expression of these proteins. Additionally, glyphosate has been shown to interfere with the growth of bacteria strains that typically colonize the human gut. Glyphosate has been shown to cross the intestinal barrier, be absorbed by the body and excreted in feces and urine.
The Role of Stress
Activation of the sympathetic (fight or flight) nervous system diverts blood to the extremities of the body and away from internal organs. Maintenance and repair of internal organs is deferred in order to use available energy, oxygen and blood to run or fight the potential threat. Chronic stress impairs the digestive system’s ability to repair itself. Over time, this can lead to leaky gut syndrome, as the body has been unable to repair damage to the tight junctions. Additionally, eating a meal while blood is diverted away from digestion, impairs digestive function and leads to an increased release of toxic metabolites. Toxic metabolites from digestion can cause damage to epithelial tissue as well.
Irritants: Alcohol, Food Additives, Agrochemicals and Medications
Unfortunately, we live in a time where our food is literally sprayed with poisonous substances that kill life. Glyphosate is the most ubiquitous agrochemical with a large body of research supporting the toxicity of glyphosate to the human body. There are too many other agrochemicals to discuss; that goes beyond the scope of this article. All that must be said is that any agrochemical that kills life is harmful to the living tissue to which it is exposed. To make matters worse, processed foods contain numerous additives that are poorly regulated with an “innocent until proven guilty” attitude. There are currently 10,000 food additives approved by the FDA. We do not live in a world where everything that is sold to us is safe for human consumption. This is evident in the number of additives/ chemicals that are being found to be toxic after decades of being widely present in food. Many food additives can injure intestinal mucosa and cause inflammation of the GI tract. Medications such as non-steroidal anti-inflammatories, aspirin and Motrin have been shown to “mutilate” the brush border of the small intestine; permitting microbes, contaminants and partially-digested food-particles to enter the bloodstream. Birth control and steroid medications have also been shown to damage the intestinal lining and contribute to conditions that allow fungal life to flourish. Alcohol consumption can also contribute to leaky gut syndrome as it creates a heavy detoxification burden for the liver, impairing its ability to produce bile, an important digestive juice. Decreased bile secretion impairs the body’s ability to digest food, leading to increased harmful metabolites, undigested food, and damage to intestinal mucosa. Additionally, food allergies can both cause and be caused by leaky gut syndrome. Removing irritating allergens is paramount to allowing the gut to heal. People with Celiac’s disease have been shown to produce more zonulin protein as a metabolite of gluten digestion. Zondulin has been shown to increase gut permeability.
The Importance of the Microbiome for Intestinal Integrity
The gut microbiota produces fermentation products that can either reinforce the integrity of the intestinal tissue or undermine the strength of the tight junctions. The fermentation products of the helpful bacteria exert a healing effect on the intestinal epithelium. Additionally, these fermentation products modulate anti-inflammatory activity which helps modulate the immune response. For these reasons, studies have shown that the administration of probiotics and prebiotics can help reverse leaky gut syndrome by treating dysbiosis.
A discussion of the pathogenesis of leaky gut and autoimmune disease is not complete without mentioning the role that the digestive system plays in our immune function. Our digestive system directly interfaces with the outside world and is responsible for detecting and destroying potential pathogens as well as communicating threats to the systemic immune system. As such, there are many immune cells in our gut as well as patches of lymphoid tissue called Peyer’s patches that are responsible for immune surveillance and keeping pathogens at bay. Under the conditions of leaky gut, an immune response ensues. Chronic inflammation and intestinal damage results in continuous immune activation signals from the immune cells of the gut. This mechanism throws the immune system out of homeostasis and paves the way to autoimmunity.
Diagnosing Leaky Gut
There are a few different laboratory tests that can help confirm a potential leaky gut syndrome.
1. Mannitol & Lactulose Test
2. LPS/Occludin/Zonulin/Actomyosin protein antibody test
3. Direct Zonulin measurement-
Symptoms that could indicate leaky gut include: chronic joint pain, fatigue/ brain fog, indigestion, recurrent bladder infections or yeast infections, gas/ bloating, diarrhea or constipation, insomnia, mood swings, bad breath and autoimmune.
Healing Leaky Gut
To heal leaky gut we must remove the triggers and address potential causes of damage to the epithelial lining of the gastrointestinal tract. These triggers could be:
food allergies and sensitivities
chemical additives in processed foods
food contaminated with pesticides, antibiotics or steroids
NSAID medications, antibiotics, birth control, acid blockers, other pharmaceuticals
excessive alcohol
emotional or physical stress or trauma
inflammatory vegetable seed oils (canola, sunflower)
poor diet
microbial imbalance: dysbiosis, SIBO (small intestine bacterial overgrowth), yeast, parasites
Contaminated water: Most (probably all) tap water is contaminated with low levels of pharmaceuticals, pesticides, acids, chemical cleaning agents and more. It is paramount to drink at least 2 litres of clean, mineralised water every day. Investing in a reverse-osmosis filter with a remineralization attachment is incredibly important to heal leaky gut and other health conditions.
Another key component of healing leaky gut is to restore the integrity of the intestinal epithelium and protective mucosa. The following supplements and foods can be supportive:
L-Glutamine: an amino acid that is the prime energy source for intestinal cells and can aid in healing digestive lining. 5-10g of powder 2x/per day for at least 1 month.
Collagen protein: the main structural protein of all connective tissue. Buy high quality hydrolyzed bovine or marine collagen.
Vitamin C: important for the synthesis of connective tissue.
Zinc Carnosine: up to 30mg/day. Important mineral in the synthesis of collagen. Aids in healing digestive lining and healing ulcers. Consume with food.
Mineral dense foods: vegetable juices, soups and broths, seaweeds
Bone broth: the original superfood! High source of minerals and collagen that our body needs to build new connective tissue
Probiotic supplements and foods: sauerkraut, yogurt, kefir, pickled seaweeds and vegetables, miso
Prebiotic foods (fibre): fibre is the food for our bacterial allies! Reinoculation of good bacteria is not enough; we must also feed the bacteria what they want and keep their populations well fed and happy! Root vegetables are a great source: burdock, carrots, turnips, cabbage, celery, grains, chia, flack, chicory root.
The importance of the healing power of herbal teas in reversing leaky gut cannot be overstated. Drinking tea is the equivalent of bathing the intestines in healing waters. Be sure to brew your tea with clean and mineral-containing water. The following herbs can be very helpful:
Marshmallow: cold-brew
Licorice: avoid in high blood pressure and pregnancy
Cinnamon: cold-brew
Meadowsweet: especially if there are ulcers present.
Gotu Kola: specifically indicated if there is an emotional/ stress-induced intestinal damage or nervous belly.
Horsetail: mineral dense connective tissue tonic
Oregon Grape root: specifically indicated if dysbiosis is a cause of leaky gut. Additionally, if there is liver stagnation, toxin exposure or alcohol influences.
Seaweed: high in minerals and soothing quality that nourishes the mucosa of the gut
Plantain: encourages new cell growth and tissue repair
Calendula: particularly if there is a fungal/ yeast imbalance, dysbiosis, or SIBO.
Herbal medicines are helpful for healing leaky gut as well as modulating a dysregulated immune system. Reach out for a consultation if you are seeking specific support for your digestive or autoimmune challenge.
As always, this is for educational purposes only and does not substitute for medical advice. Always ask your doctor for medical advice.