Our digestive health has a lot to do with our immune health and vice versa. Its role in maintaining our immune health and, eventually, our overall wellbeing cannot be underestimated. The two systems work closely to keep us in good physical and mental shape.
The immune system is the group of cells and molecules that protect us from disease by monitoring our body and responding to any foreign (non-self) substances they perceive as threats, particularly infectious microbes, viruses and parasites that can get into our digestive system and gut.
Our immune system has co-evolved along with diverse gut flora, not only to create defences against pathogens, but also to develop tolerance for beneficial microbes. As a consequence, the immune system and the gut microbiota developed a mutualistic relationship, regulating one another and cooperating to support each other.
The importance of this interaction is clearly highlighted by the fact that 70–80% of the body’s immune cells are found in the gut.
The cells of the immune system patrol our body looking for threats such as microbes and devise quick immune responses when they find them that aim to destroy the foreign cells.
Part of a healthy immune response is to create inflammation at the site of an injury to help with the healing process. This inflammatory immune response should then die down shortly after. What is not healthy is when the immune system is constantly creating inflammation in the body and reacting to things that are not actually a threat, such as food. If the immune system goes into overdrive dealing with microbial gut infestations or food intolerances then it becomes distracted from other more serious issues, and this is where we can see weakened and dysregulated immune systems in people, and also auto-immune conditions where the immune system starts to attack its own tissue, mistaking it for ‘non-self’.
GALT– what is it, and what role does it play?
GALT stands for gut-associated lymphoid tissue. It is the largest immune organ in the body and is the primary route by which we are exposed to antigens. The intestine is home to our GALT and it is essentially the first line defence of our immune system, which serves to protect our bloodstream from foreign invaders. The GALT includes Peyer’s patches (groupings of lymphoid follicles in the mucus membrane that lines your small intestine. Peyer’s patches play an important role in immune surveillance of materials within your digestive system), the appendix, and scattered lymphoid follicles.
When working correctly, our GALT will target and destroy unwanted organisms such as pathogenic bugs, viruses and parasites that have made their way into the intestine. It is also able to decipher between pathogens and beneficial bacteria.
If our GALT gets damaged by pathogens (think food poisoning or drugs like antibiotics), high levels of inflammation can occur, causing injury to the intestinal lining. This means that particles that normally wouldn’t be allowed into the bloodstream by the GALT will pass through, resulting in an additional inflammatory response. This is often called ‘leaky’ gut or gut intestinal hyperpermeability.
Let’s look some more at ‘leaky’ gut
Leaky gut syndrome is a digestive condition that affects the lining of the intestines. Tight openings in the intestinal walls allow water and nutrients to pass through into the bloodstream while keeping harmful substances inside.
In leaky gut syndrome, these openings become wider, allowing food particles, bacteria, parasites and toxins to enter directly into the bloodstream. The foreign substances entering the blood can cause an autoimmune response in the body, including inflammatory and allergic reactions such as migraines, irritable bowel, eczema, chronic fatigue, food allergies, rheumatoid arthritis and more.
Our modern lifestyle is inundated with toxic foods, medications, infections, chemicals, and let’s not forget chronic stress that often comes hand in hand with these. Inflammatory foods include dairy, grains, and eggs, and toxic foods include things like sugar, alcohol, and those that have been genetically modified. The presence of any of these in our diets may be major contributors to damaged intestinal barrier function.
The most common types of infections are yeast infections, intestinal parasites, and small intestinal bacteria overgrowth (SIBO). Essentially, the bad bacteria take over our gut and become the dominant species, and this imbalance can also contribute to the degradation and breakdown of the gut wall.
Environmental toxins can also play a role in leaky gut, like the presence of mercury (heavy metal toxicity), plastics, and bisphenol (BPA). Toxins can also include some of the medications we take on a daily basis, including non-steroidal anti-inflammatories, steroids, antibiotics, birth control, and the strong proton pump inhibitor antacids that were not really designed to be taken long-term on a daily basis.
Chronic stress directly causes inflammation and, potentially, the development of leaky gut syndrome. Continual stress will decrease the effectiveness of your immune system, making it more difficult for your body to fight pathogenic bacteria and viruses, leading to more systemic inflammation, including the gut lining.
The integrity of the intestinal barrier is fundamental for a healthy relationship with the gut microbiota and a healthy inflammatory-immune response.
Leaky gut and autoimmune diseases
If you have a leaky gut, think about all the toxins and food particles entering your bloodstream. Your immune system will tag them as foreign matter and remember them as a threat for next time they enter. It creates a system-wide inflammatory response to address the intruders.
If your gut continues to be leaky, your immune system continues to send more and more inflammation to the area to try to get rid of the foreign material. Eventually, it cannot keep up with demands and begins sending waves of inflammation even without a threat being present. It is thought that this can lead to autoimmune conditions as your own tissues and organs become the target of your own immune system.
Your immune system will begin producing antibodies against the foreign substances in your blood – the problem is many of the invaders look very similar to your body’s own cells. Because of this, your immune system will start sending out antibodies to attack your own tissues. This is called ‘molecular mimicry’. The type of autoimmune condition that manifests (and of course, there may be more than one) depends on the tissues being attacked. If the joints are being affected, rheumatoid arthritis is the result. If it’s the thyroid gland, the result is usually Hashimoto’s or Graves’. If it’s the gut lining, Crohn’s or colitis may develop. If it’s the skin, you may develop skin conditions, such as eczema or psoriasis.
Diet and supplements to improve gut barrier function
Gut microbes get most of their nutrients from our diet, and help us digest much of the food we ingest too! Therefore, it should come as no surprise that diet has a huge impact on the composition of the gut microbiome and, consequently, on our immune system.
Diet influences many aspects of the microbiome-immune system crosstalk, including, for example, the permeability of the intestinal barrier.
Short chain fatty acids are one of the reasons why fibre-rich diets support our immune system.
They are produced when the friendly gut bacteria ferment fibre in your colon and are the main source of energy for the cells lining your colon. For this reason, they play an important role in colon health. High-fibre foods, such as fruits, veggies, legumes and whole grains, encourage the production of short-chain fatty acids.
You can get additional fibre in your diet by taking my two of my Fibre tablets half an hour before meals daily, with a full glass of water. Try to aim for 30g per day.
Garlic has been used for decades as a natural antibiotic, antifungal and antiparasitic, and can work really well to deal with gut infestations. I recommend taking one of my high-strength Garlic tablets daily to help eradicate pathogenic bacteria, fungi and yeasts in the body.
My best-selling Live Bacteria capsules contain beneficial strains of bacteria that help to populate the microbiome with friendly bacteria, crowding out the harmful bacteria, reducing gut inflammation and strengthening the immune system.
Omega 3 healing fats
In particular, aim to consume the omega 3 fats, such as oily fish, chia seeds, flaxseeds, walnuts to nourish the cells in the gut. If you find you cannot get these through your diet, you can take one of my high strength Omega 3 fish oil capsules daily with food.
If you suspect you have parasites, you may want to consider carrying out a Charcoal ‘deep-clean’ of your gut. You can read more about this in my post ‘The benefits of charcoal cleansing’ here and you can buy my charcoal capsules by clicking on the image.
Collagen and bone broth
Both of these are excellent for restoring the integrity of the gut wall. You can make your own bone broth or purchase bone broth from a trusted source like Coombe Farm Organics.
These contain beneficial bacteria and are a great addition to a gut healing protocol. Here is my home-made sauerkraut recipe.
If you suffer with IBS, chronic bloating, skin problems and any auto-immune disease, try eliminating gluten from your diet. Gluten contains a protein called zonulin which breaks down the glue that keeps the junctions in the gut tight, thus increasing the risk of leaky gut and allowing foreign matter into the blood stream and creating inflammation.
Manage your stress levels
This is really important due to the link between intestinal permeability and stress. Try to carve out time for yourself, time to breathe, meditate, do something that helps you to relax.
Try functional testing
This is absolutely key in getting to the root cause of a digestive issue. Functional stool tests can help to identify the presence of pathogenic bacteria, parasites or pathogenic yeasts in the gut. These microbes can weaken your gut barrier, and ultimately your immune system, so it is important to deal with these. If you’ve tried changing your diet, eating more fermented foods, taking supplements and you are still getting symptoms, having some functional gut tests would be the next step. You would need to access testing through a nutritional therapist, naturopath or a medical herbalist.
You can download a large selection of free gut-friendly recipes from my website by clicking on the image below. In particular, I would recommend the following as they are all high in fibre, high in antioxidants and gut-healing nutrients and so will help to boost your immunity:
- Pear and Walnut Oatmeal bowl
- Green Coconut Smoothie
- Gut healing Spiced Celery Soup
- Bone Broth
- Salmon with Miso Vegetables
- Rice, Bean and Kale Bowl with Lemon-Dill Tahini
- Salmon, Coconut and Turmeric Curry
- Hemp and Tahini Bliss Balls
- Anti-inflammatory Turmeric Energy Balls
Check out all 84 of my free recipes here:
Join my Tummy Talk Facebook community here for more digestive and gut-related support by clicking on the image below.