Did you know that SIBO is an autoimmune disease? 

Are you experiencing bloating, pain and unpredictable bowel habits? If so, it might result from a condition known as small intestinal bacterial overgrowth (SIBO). 


What causes small intestinal bacterial overgrowth (SIBO)?

SIBO is a complex condition but many of the symptoms result from friendly gut bacteria - which are (in most instances) beneficial for your digestive system - not moving from the small intestine to lower down the digestive tract in the colon.

Our old friends the healthy bacteria give off gases as they ferment the food we eat and, as a result, you end up with that uncomfortable bloating after eating and having to move your belt buckle down a notch!

What's the connection between SIBO and autoimmune disease?

So, how is SIBO related to autoimmune disease, you may ask? The relation between SIBO and autoimmune disease is what I will be explaining to you today. Not all SIBO is caused by autoimmune disease but, if you are experiencing gut symptoms and are struggling to find the root cause, listen up, as this might be the answer you were looking for all along. 

The migrating motor complex

The migrating motor complex (MMC) is crucial in the development of SIBO. When you eat and digest food, your small intestine needs to be cleaned afterwards, like washing the dishes after a meal, and that is the critical role of MMC. Through electromechanical activity and stimulation of the interstitial cells of Cajal - the pacemaker cells of the small intestine - the small intestine performs a sweeping action to remove any undigested foods and bacteria. 

There are several reasons that the migrating motor complex might not function optimally. These include:

  • damage to the pacemaker cells
  • adhesions affecting the small intestine due to surgeries, injury or inflammation
  • an autoimmune response following food poisoning or traveller’s diarrhoea

Why trigger the autoimmune response?

The cause of autoimmune disease is complex, but we know that those who have had food poisoning may be more susceptible to an autoimmune response in the small intestine. You may be more sensitive to an autoimmune response if you already have a diagnosed autoimmune condition or a family history of autoimmune disease.

In SIBO, the inflammatory reaction is to a cytoskeletal protein that damages the interstitial cells of Cajal, causing impairment to the MMC. As a result, the washing of the small intestine of food and bacteria is sloppy, leaving you left with dirty dishes. 

Without delving too much into the immunological mechanism, bacterial food poisoning triggers autoimmune disease through a process known as molecular mimicry. In this process, the toxin released by the pathogenic bacteria during the acute infection has a similar pattern on its surface to that of a self protein found in the interstitial cells of Cajal, called vinculin.

As a result, your immune system not only attacks the cause of the food poisoning but your tissue as well, as it is unable to differentiate between the two. Ultimately, this results in damage to the small intestine and a deficient MMC, which becomes activated long-term, not just during the acute phase of illness. 

Autoimmune protocol vs low FODMAP

Most of the time, when you are diagnosed with SIBO, you are encouraged to go on a low FODMAP diet to help with symptoms. FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols, short-chain carbohydrates (sugars) that the small intestine absorbs poorly. As a result, any bacteria wrongly lodged in the small intestine will ferment these carbohydrates and create gases, which cause discomfort and pain. If you decrease these foods, the less food for the bacteria to ferment, and as a result, your symptoms appease. 

But, have you got to the root of the problem? Unfortunately not. There is a place for a low carbohydrate diet as part of healing and maintenance of SIBO, but it isn’t addressing the root cause, and that’s where an autoimmune protocol might be a better approach for long-term therapy. 

The first steps to healing SIBO

If you have symptoms of SIBO, then the first thing to do is get a SIBO breath test which you will be able to get with your doctor or a registered nutritionist. This test will indicate whether you have bacteria (and the gases they produce) in your small intestine. If you have a positive SIBO result, then you need to understand the underlying root cause of your condition. If your health practitioner suspects that there might be an autoimmune reaction at play, you can test for these autoantibodies in your bloodstream. 

In the meantime, whilst you determine the cause of your gut issues, you could try a more ketogenic-type diet by limiting your carbohydrate intake and increasing your healthy fats. This diet will provide you with short-term relief from the unpleasant symptoms of SIBO, such as bloating and may help establish a healthy immune system if this is an underlying factor in your condition.

The views expressed in this article are those of the author. All articles published on Nutritionist Resource are reviewed by our editorial team.

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London W1G & Harrogate HG1
Written by V. J. Hamilton, Autoimmune Disease Expert | BSc (Immunology), DipION, mBANT
London W1G & Harrogate HG1

After 25 years of suffering from multiple autoimmune conditions that affected her energy, skin & hair, VJ discovered she could uncover the root cause of her issues to transform her health & live without symptoms.

VJ now uses these same principles to help women with autoimmune disease regain their strength & live a whole and symptom-free life.

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