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Autoimmune and SIBO 101

In previous blogs, we’ve briefly chatted about in the past, leaky gut (abnormally increased permeability of the small intestine) can cause inflammation in the body and gut, further increasing permeability and triggering food sensitivities and autoimmunity. As a result of the presence of leaky gut, small intestinal bowel overgrowth (SIBO) can take place.

SIBO is the acronym for Small Intestine Bacterial Overgrowth and happens when there is an increase in the number of bacteria and/or changes in the types of bacteria in your gut. Studies show in a majority of SIBO cases this overgrowth is caused by bacteria that should be in the large intestine, not from the few bacteria in the small intestine.

The overgrown bacteria “eat” sugars, through fermentation, found in specific foods we eat. The fermentation produces gases, and it is those gases that create the uncomfortable symptoms of the SIBO.

What do SIBO Symptoms Look Like?

Those with SIBO may not know they have it but could tell you all about the uncomfortable symptoms they are experiencing. Some of these symptoms are:

Abdominal pain and cramping

Bloating (which can severely distend the abdomen)

Diarrhea, constipation, or both




Weight loss and nutrient deficiencies (in severe cases)

So what causes SIBO?

The causes of SIBO are complex and vary from one person to the next. A healthy digestive system requires a highly acidic environment in the stomach to break down food and act as a first-line defense against bad bacteria. There are many different reasons someone might have SIBO but due to glaring symptoms, the most obvious is diet itself. A diet that is high in sugar, refined carbohydrates, and alcohol (even moderate consumption can feed specific bacterial strains causing overgrowth) can cause damage in the small intestine, but it can also set the stage for SIBO.

Now what?

If you’ve had or experienced any of the following, plus have any of the above-mentioned symptoms, it might be appropriate for you to connect with a doctor to pursue testing and treatment:

issues of the digestive tract (diverticulosis, inflammatory bowel disease, gastric bypass surgery, or other GI surgeries, especially any that resulted in removal of the ileocecal valve or gall bladder, scarring or adhesions)

Medication use that impacts the digestive tract (narcotics or any others that slow motility, PPIs, H2 blockers, antibiotics, birth control pills)

Autoimmune diseases that impact motility or cause digestive tract damage (diabetes, long-standing celiac disease, lupus, scleroderma, Crohn’s, ulcerative colitis, Hashimoto’s, endometriosis of the bowel, etc.)

Lowered immune system function (HIV, immunoglobulin A deficiency, etc.)

A history of eating disorders