This is part 2 of a three-part blog series covering the ins and outs of autoimmune disorders. Part 1 explained that autoimmune diseases are an unspoken epidemic affecting far more people than is currently realized. In the present article, we will discuss the connection between leaky gut, immune system function, and autoimmune disease. In part 3 we will take a closer look at the current research demonstrating how diet and gut health are intimately connected to autoimmunity, and how a Paleo diet can be used to overcome most, if not all autoimmune disorders.
The Gut Wall is Our Most Important Barrier to the Outside World
Did you know that the average person swallows enough pathogenic (disease-causing) bacteria each day to make over 1,000 people sick?! Did you know that the gastrointestinal (GI) tract is our first and foremost line of defense against the millions of bacteria, viruses, yeasts, fungi, parasites, parasite eggs, and other toxins that we inadvertently swallow during the course of each day? And did you know that the GI tract (from stomach to anus) is only one cell layer thick?!
A single layer of cells known as the gut wall (gut lining) constitutes the most important physical barrier that separates our bloodstream from the milieu of toxins constantly traveling through our digestive systems. It’s sort of horrifying to think about all the microorganisms we swallow on a daily basis, and it’s even creepier to realize that these buggers only need to worm their way through one teeny tiny layer of cells (the gut wall) to gain access to the inside of our bodies.
Considering all of this, it seems extremely important to maintain the health of our gut lining, and to do everything in our power to keep the contents of our intestines sealed off from the rest of our bodies. Maybe that’s why a healthy body uses over 20% of the energy derived from food to maintain the integrity of the gut lining, completely replacing it every 1-4 days. Apparently the body thinks it’s really important to have a healthy gut! Maybe that’s because the majority of our immune system (70-80%) is located in and around the gut wall!
Normal Immune System Function
So what happens when a toxic invader manages its way inside the body, by passing through the gut wall or otherwise? The immune system is triggered ‘on’ and starts producing inflammation and other chemicals that quickly go to work destroying anything deemed as non-self. When all of the foreign invaders have been executed, the inflammation dissipates, and the immune system goes on standby again. This is a very simplified explanation of a normal immune system response.
An equally simple definition of an autoimmune disorder is when a person’s immune system becomes overactive and spends too much time ‘on.’ An immune system that won’t turn off loses it’s ability to differentiate between the ‘bad guys’ and the ‘good guys’ and goes berserk attacking anything and everything in sight.
Autoimmunity: Immune System SNAFU
As discussed in part 1, the incidence of autoimmunity is a seriously under-emphasized modern-day epidemic that is occurring to some degree in nearly every single person. In autoimmune disease states, the immune system loses its ability to distinguish between harmful foreign invaders and the body’s own healthy tissues. As a result, it mistakenly creates antibodies that are directed against the self (autoantibodies) that can cause all sorts of damage to healthy cells and organs.
Stated simply, an autoimmune disease/disorder is the result of an immune system gone haywire that won’t turn ‘off’. The chronic inflammation produced from an ongoing immune response also causes tissue damage by suffocating healthy cells. This destruction of healthy tissues by autoantibodies and chronic inflammation is responsible for the characteristic symptoms of all autoimmune diseases, which include pain and inflammation. For all intents and purposes, the main feature that differentiates the various autoimmune diseases from one another is simply the part of the body (the type of tissue) that is under attack by one’s own immune system.
Modern medicine treats all autoimmune diseases essentially the same: with anti-inflammatory and immune-suppressing medications that block the natural immune system response. It goes without saying that some serious and life-threatening side-effects can and do result from shutting off the immune system. I made the personal decision to go against the recommendations of my Rheumatologist doctors and to not take prescription medications to treat my autoimmune diseases. Instead I did a little research, realized that my autoimmunity was resulting from a leaky gut, went Paleo , healed my leaky gut, and put my multiple autoimmune disorders into remission….but I’m getting ahead of myself. For now, let’s learn about what in the heck a leaky gut is.
The gut has a tough job. It must somehow allow for the uptake of water and nutrients from food (through the gut wall), while simultaneously preventing toxins from gaining access into the body. Our first major line of defense against the toxins we swallow comes from our stomach acid. The majority of pathogens that come into contact with our stomach acid go down like a toon in toon acid (remember Roger Rabbit?). That’s why medications that lower stomach acid (i.e. antacids, PPIs, etc.) can readily lead to bacterial overgrowth. Low stomach acid production is also a common cause of malnutrition because stomach acid is needed to digest protein and unlock the vitamins and minerals that are bound to the proteins in food. When stomach acid production is low (termed hypochlorhydria), many ‘critters’ are able to survive the normally fatal journey through the stomach and make their way into the next part of the digestive tract…the small intestine.
The small intestine is a super important segment of the GI tract where the majority of nutrients from food are absorbed into the bloodstream through specialized channels in the gut wall. It’s also a major area of bacterial growth. Did you know that the average person carries around 2-3 pounds of bacteria in their intestines?! Ideally this “microflora” (AKA gut flora) is made up of mostly ‘good’ bacteria, known as “probiotics.” In a healthy body, the vast majority of toxins and unwanted guests pass through the GI tract unabsorbed and are excreted from the body without causing much harm.
These days a “healthy gut” is truly becoming a rare phenomenon. Our high carbohydrate diets contain excess dietary sugars that create a feeding frenzy for the unfavorable bacteria in our guts. Poor or sluggish digestion can also lead to overgrowth of pathogenic bacteria within the intestines. Perhaps the most detrimental blow to our microflora comes from the overuse of antibiotics by both humans and the animals we eat. Not only do antibiotics destroy the healthy bacteria in our guts, they also contribute to the creation of super-bacteria that are resistant to our drugs, which is basically the stuff nightmares are made of. When the gut’s microflora becomes imbalanced, it is called “dysbiosis.”
A leaky gut is basically what it sounds like: your intestines develop tiny holes that allow for the gut contents to slowly leak through the gut wall and into the body. It’s not difficult to imagine that if the gut remains ‘leaky’ and toxins are continually flooding into the body, that the immune system (being located mainly in the gut) will be turned ‘on’ most of the time. Eventually the gut’s immune system will become overwhelmed and unable to cope with the massive influx of toxins leaking in. At this point the cascade of particles flowing through the gut wall can gain access to the bloodstream, and travel to virtually any part of the body, inciting an inflammatory immune response wherever they ‘land.’ (Sounds a lot like autoimmunity, doesn’t it?)
So what causes a leaky gut you ask? Unfortunately lots of things can. Some usual suspects include pharmaceuticals (such as NSAIDs, aspirin, antibiotics, etc.), alcohol, stress, various toxins, poor digestive function, infections, pathogens, and chemicals that are naturally contained within plants (especially seeds). Research over the past decade has correlated several potential triggers with a leaky gut, however:
Two main gut irritants have been repeatedly demonstrated to significantly increase ‘intestinal hyperpermeability’ (the sciencey term for leaky gut) in EVERYONE:
- 1. Gluten and gliadin from gluten-containing grains, and similar proteins found in gluten-free grains and legumes
- 2. Dysbiosis (imbalanced gut bacteria)
Zonulin : The Link between Leaky Gut and Autoimmune Disease
In all humans, a molecule called zonulin is released from the gut wall when the permeability of the gut needs to be increased. For example, when we get a ‘stomach bug’, the reason that diarrhea often follows is due to the release of zonulin by the gut, which in turn increases the leakiness of the gut. This increase in gut permeability causes the body’s water supply to rapidly exit backwards through the open gut wall in an effort to flush the bad bug out of our GI tract to clear the infection from our body (hence the diarrhea). The point is that there are reasons why the body needs to be able to control the permeability of the gut, but a healthy gut stays closed most of the time.
Dysbiosis and gluten are well documented to induce the release of zonulin from the gut cells, and to elicit leaky gut syndrome in everyone. However people with autoimmune diseases are particularly affected by this phenomenon. For example, the consumption of gluten causes a significantly greater release of zonulin from the intestines of those with autoimmune diseases compared to healthy individuals. Only in the past decade or so has our science and technology caught up to our antiquated understanding of how a leaky gut can lie at the root of many disease states including autoimmunity. Thanks to the Human Genome Project, researchers have mapped most autoimmune diseases to chromosome 16, which also happens to be the chromosome that codes for the production of zonulin. This discovery has allowed scientists to use zonulin as the only known biomarker for autoimmune diseases.
Basically what this means is that eating grains and legumes causes leaky gut by increasing the production of zonulin from the gut wall in both ‘healthy’ and autoimmune individuals. Scientists can measure the amount of zonulin released by the gut and correlate it to the severity of a person’s autoimmune disease. The more zonulin that’s released, the greater the extent of leaky gut, and the higher likelihood of autoimmune disease expression. But don’t get too excited, as we don’t yet have approved tests available to measure zonulin production as a diagnostic tool. Until modern medicine catches up with the current research, our best bet in determining whether certain triggers are to blame for our autoimmunity is to simply remove the questionable triggers (i.e. grains, legumes, etc.) and to balance the gut flora, as will be further discussed in part 3.
Heal the Gut to Overcome Autoimmunity
With our most recent discovery of the molecule zonulin, it is now believed that autoimmune diseases can be stopped or reversed if the leaky gut is healed and the gut’s immune system is given the chance to recover. Zonulin production (leaky gut) stops when the gut irritants (i.e. gluten and dysbiosis) are removed. When the triggers are gone, the leaky gut can begin to repair itself, and the immune system can finally turn off. Autoimmune diseases go into remission when they are no longer being triggered by the constant influx of gut toxins that overwhelm the capacity of the immune system, which is located mostly in the gut.
The discovery that a leaky gut is a likely prerequisite for autoimmune diseases makes this one of the only known examples of a chronic disease that can be directly modified via diet and lifestyle. Despite the abundance of research now available demonstrating precisely how a leaky gut can trigger autoimmunity, many doctors and experts refuse to accept that there is a correlation between gut health and disease. Sadly, 3 of the 4 autoimmune doctors (Rheumatologists) I’ve visited have told me that my rheumatoid arthritis has nothing to do with my diet, and attribute the remission of my symptoms to “coincidence.” In the third and final article of this 3-part series we will be discussing how it’s possible to overcome virtually any autoimmune disease simply by healing our leaky gut. Until then, I’ll leave all of the non-believers out there with this quote from Arthur Schoenhauer (1788-1860):
In good health,
Kinsey Jackson, MS, CN
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