Autoimmune disease and the gut
A healthy gut needs two key components — a healthy and intact gut lining and a diverse and balanced microbiome. When these components are compromised, the gut becomes dysfunctional and over time can trigger autoimmune disease.
In my last blog post, we took a dive into autoimmune disease and some of the underlying factors that cause this immune system dysfunction. We briefly touched on the link between autoimmune disease and gut health, although research in this area is so compelling that it’s worthwhile to unpack this connection even further.
To recap, a healthy gut requires two key components:
A healthy and intact gut lining that keeps the contents of the gut e.g. food particles and toxins from escaping into the bloodstream
A diverse and balanced microbiome with healthy amounts of beneficial bacteria and no harmful bacterial or fungal overgrowth
When these components are comprised (as a result of poor diet, chronic stress, medications, environmental toxins, chemotherapy, etc.) the gut becomes dysfunctional. A permeable or ‘leaky’ gut lining allows pathogens, undigested food proteins, and toxins to leak through the intestinal barrier and into the bloodstream. Inflammation and immune system activation follow as these foreign particles are marked as threats to the body which, over time, can trigger issues such as food sensitivities and autoimmunity.
The microbiota that reside in the gastrointestinal tract further influence immune homeostasis. With 70-80% of the body’s immune cells also residing in the gut (in gut-associated lymphoid tissue), the two have a symbiotic relationship to ensure that the body is protected from any harmful pathogens it may encounter. Our gut microbes act as sensors within the intestinal epithelium and fire off signals when foreign bacteria are detected, which subsequently mobilise immune cells (such as neutrophils, macrophages, T cells and B cells) into action. When dysbiosis is present however, this process is impaired, and the gut microbiota lacks the resilience and diversity required to establish healthy and balanced immune responses.
Understanding that the health of the gut determines the health of the immune system opens up new treatment avenues for those suffering from autoimmune conditions. Practitioners may like to consider the following in addition to pain management strategies:
Investigating intestinal permeability (‘leaky gut’), and working to reduce inflammation and heal and seal the gut lining
Investigating bacterial imbalance, and working to nourish healthy gut flora and improve the diversity of microbes
From a nutritional standpoint, a good start is to reduce the consumption of inflammatory foods that damage the gut lining, such as refined carbohydrates and sugars, trans fats, processed meats and alcohol. Instead, centring the diet around antioxidant and anti-inflammatory nutrients (like the ones listed below) will help to nourish the gut lining and strengthen immunity:
Vitamin A: Carrots, apricots, pumpkin, peaches, egg yolk, green leafy vegetables
Vitamin C: Berries, citrus fruits, kiwifruit, papaya, broccoli, cauliflower
Vitamin E: Almonds, sunflower seeds, sesame seeds, extra virgin olive oil
Zinc: Oysters, shellfish, cashews, Brazil nuts, sunflower and pumpkin seeds
Omega 3s: Fish, fish oils, chia seeds, flaxseeds, walnuts, seaweed, tofu
Turmeric and ginger: Fresh or ground
Incorporating a mix of prebiotic and probiotic foods into the diet can assist in repopulating beneficial gut bacteria and improving the diversity of the microbiome. Prebiotics are special plant fibres that cannot be digested by the body but serve as food for the beneficial bacteria of the gut. Probiotics are live bacterial strains that are naturally contained in fermented foods. Some examples of both are listed below:
Prebiotics
Resistant starch: Cooked and cooled potatoes e.g. a cold potato salad
Inulin: Garlic, onion, leeks, asparagus, artichokes, green bananas, rolled oats
Pectin: Apples, citrus peels, apricots, peaches
Probiotics
Sauerkraut and kimchi
Kombucha
Yoghurts and kefir
Tofu and tempeh
Miso
References
Belkaid, Y., & Hand, T. W. (2014). Role of the microbiota in immunity and inflammation. Cell, 157(1), 121–141. https://doi.org/10.1016/j.cell.2014.03.011
Wu, H. J., & Wu, E. (2012). The role of gut microbiota in immune homeostasis and autoimmunity. Gut Microbes, 3(1), 4–14. https://doi.org/10.4161/gmic.19320
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