If you read the previous article in the autoimmune series you know that all autoimmune diseases at their core are related to immune dysfunction. So if all autoimmune diseases are related to immune dysfunction is there anything that we can do to help modulate our immunity? Today, modern research shows promising results. There are plenty of options in changing lifestyle and environmental factors that will help balance a dysfunctional immune system. To dig deeper we can ask “which single system in my body contains the most amount of my immune system?” By asking this question we can figure out which system we can target to give us our best chance at modulating immune function. The answer to this question is without a doubt, our gastrointestinal system (1).

Your gut houses around 70-80% of our total immune system

That is a large portion of your immune system! What part of your body is constantly being exposed to different compounds from our outside world? It’s your gut! The food we eat, whether you like it or not, is riddled with hundreds of thousands of bacterial cells. Your immune system is constantly patrolling the perimeter of your gut to make sure your body is absorbing nutrients from food and not allowing any pathogens into your body. It does this all day long. If you think about your body’s design it makes sense to have our immune system trafficking your gut. Just like security at an airport, we need to let things in that are deemed safe and keep things out that may be dangerous or potentially harmful.

There are 3 primary ways to help dampen immune over activity in your gut:

• Decrease the amount of inflammatory particles entering your gut
• Increase the integrity of your gut barrier
• Increase the amount and proportion of healthy GI bacteria

Decrease the Amount of Inflammatory Particles Entering Your Gut

There is no question that Americans live a very inflammatory lifestyle. The modern “Westernized” diet has been associated with an increase in both inflammation and autoimmune diseases (2). Today we eat more starchy grains, sugars, salty foods than every before. We also eat more pro-inflammatory omega-6 fats and not enough anti-inflammatory omega-3 fats. One paper quoted (3):

“Dietary patterns high in refined starches, sugar, and saturated and trans-fatty acids, poor in natural antioxidants and fiber from fruits, vegetables, and whole grains, and poor in omega-3 fatty acids may cause an activation of the innate immune system, most likely by an excessive production of proinflammatory cytokines associated with a reduced production of anti-inflammatory cytokines.”

Proinflmmatory cytokines are being looked at as the potential link between GI dysfunction and other disorders in the body. Some people may have GI dysfunction but have no GI symptoms whatsoever. Instead the symptoms manifest as brain fog, fatigue or autoimmunity. All of these are magnified with an elevation of pro-inflammatory cytokines.

What are Cytokines?

Cytokines are simply chemical messengers that can affect the behavior of certain cells downstream. When someone’s gut is inflamed, much of that inflammation will initially stay in the gut. At this point our immune system has been activated. When our immune system is active it releases cytokines systemically, which can affect the activity of the immune system elsewhere. These cytokines can prime other portions of the immune system in different locations such as the brain, joints, thyroid and more. Recent studies have shown a link between higher levels of inflammatory cytokines and autoimmune diseases (4,5). There is certainly no surprise here.

So if your diet is causing elevate levels of cytokines, can we lower cytokines with diet too? Most functional medicine practitioners agree that diet affects a huge portion of our health. Many practitioners use diets such as the Paleo Autoimmune protocol, GAPS, SCD or FODMAPs to help lower unwanted inflammatory responses. We use a similar approach here with our patients with autoimmune diseases. The goal is to lower the overall amount of inflammatory particles that enter the body so we can decrease the amount of inflammatory cytokines and therefore decrease overall immune reactivity.

Increasing the Integrity of Your Gut Barrier

Your gut barrier is one of the most fragile barriers in your body. Because the majority of your immune system surrounds your gut barrier, one of the best ways that we can decrease the amount of contact our immune system has with these inflammatory particles is to increase the integrity of the barrier that separates our blood from the contents in our intestine.  While we all have some permeability in our gut barrier, those with excessive intestinal permeability have increased risk of autoimmune diseases (6,7,8,9,10).
What was thought to be a self-perpetuating process in autoimmune disease now shows promise that the damage from an autoimmune disease can potentially be stopped. One researcher believes that autoimmunity can potentially be reversed by increasing the strength and integrity of the gut barrier (10).

So what can we do to increase the strength of the gut barrier?

One of the best nutrients for gut barrier integrity is glutamine. Glutamine has been shown to be low in people with leaky gut(9), and glutamine is considered to be one of the main sources of fuel for our enterocytes (also known as gut cells) (11). Another key nutrient is zinc. Zinc has been shown to decrease leaky gut in certain autoimmune diseases as well as reduce the risk of relapse (12).

A way we can decrease leaky gut without the use of nutrients is to increase neuronal firing of the lower brainstem. In the lower brainstem originates a nerve called the vagus nerve. Studies have shown that the more “tone” you have in your vagus nerve the stronger your gut barrier is and the lower your inflammatory levels are (13,14). There will be more in depth review on this topic in a later article.

Increase the Amount and Proportion of Your Healthy Gut Bacteria

There is a tremendous amount of new research that is exploring how our gut bacteria affects our overall well-being. We have so much bacteria in our GI tract that recent research is saying that we have at least as many bacterial cells on or in us as we do human cells (15)  We may even have up to 10 times the amount of bacterial cells on us that we do human cells (16). These bacteria can play a role in either promoting or destroying good health. There have been numerous studies showing an altered balance of bacteria in people with autoimmune diseases (17,18,19,20,21,22,23). Healthy bacteria have been shown to secrete compounds that can help re-balance a previously imbalanced immune system. Your good bacteria have been shown to release metabolites called Short Chain Fatty acids (SCFA). These SCFA have been shown to enhance a cell in our immune system called a T-regulatory cell which has been shown to help decrease autoimmunity (24).