SIBO: The Common Root Cause of IBS

Dr. Preet Kangura, ND 

Small intestinal bacterial overgrowth (SIBO) has continually been shown to be the root cause of IBS. 70 – 80% of people, who have been diagnosed with Irritable Bowel Syndrome (IBS), will test positive for SIBO. Before explaining why this is a crucial finding, let’s take a quick look at what much of the medical field calls IBS.

Irritable bowel syndrome is what I like to call a “lazy diagnosis”. The reason I describe it in such a manner is because when patients complain of digestive issues such as excess burping and/or flatulence, abdominal bloating, abdominal cramping, diarrhea, constipation, and there is no inflammation or lesions to be found in the gastrointestinal tract, many doctors give up on finding the root cause of the symptoms and label the patient as having a “syndrome” – an irritable bowel syndrome to be exact. Treatment options are usually minimal and directed only towards reducing symptoms on a daily basis.

Our intestines are divided into two groups – small intestines and the large intestine (aka colon). Food is digested down into its simple, absorbable components in the small intestines, while the waste is pushed into the large intestine for eventual evacuation during bowel movements. In regards to our gut bacteria, about 80% of them are meant to reside in our large intestine, while only about 20% in our small intestines. In SIBO, much more than 20% are residing in the small intestine, and this creates havoc with our digestive processes. The primary cause of bacteria over growing in our small intestines is a dysfunctional migrating motor complex (MMC). The MMC controls the wave-like movement that pushes food waste along the small intestines and into the large intestine, where it is eventually evacuated by a bowel movement. However, this strong movement also ensures to keep our bacteria in our large intestine and inhibits them from travelling retrograde up into our small intestines.

How do excess bacteria in the wrong place cause IBS symptoms? Well, the bacteria’s primary food sources are polysaccharides and fiber. Therefore, the bacteria go after certain sugars, most grains, and a wide range of foods high in fiber when you eat them. As mentioned earlier, the small intestines are where our food is digested down for nutrient absorption. However, once the bacteria intervene in this process, it causes fermentation of the improperly digested food to occur. This fermentation leads to excessive gas to build up, which ultimately causes the multitude of indigestion symptoms that fall under the label of IBS. Bowel movements end up changing to loose/diarrhea or of the constipated type due to inefficient digestion of food and production of certain gases by the bacteria that can further inhibit proper motility of the GI tract.

SIBO is not only considered the likely root cause of the majority of IBS cases, but it has also been very much correlated with conditions such as rosacea, non-alcoholic fatty liver, heart burn, malnutrition, and food sensitivities. The connection between rosacea and SIBO drives home the point that when the gut is being offended, even the skin can become unhealthy. And yes, rosacea does significantly improve, and in some cases, fully resolve when the SIBO is treated properly.

Before treatment of SIBO, one must have a proper diagnosis. The gold standard, non-invasive testing for SIBO is now offered in house here at Sage Clinic, via a hydrogen and methane breath test. Once diagnosed, proper treatment is absolutely crucial to the short term, and even more importantly, the long term resolution of SIBO and the symptoms it leads to. I take great pride in treating SIBO in a manner that not only addresses the overgrowth, but also targets the reason why the patient ended up with SIBO in the first place. There are many great treatment options for SIBO, and here at Sage, we offer the right treatment based on your specific case – whether it is herbal or pharmaceutical.

It has brought me great pleasure to see patient’s 10 – 20 year history of “IBS” completely disappear after treatment for their SIBO. If you have been dealing with chronic digestive issues, testing for SIBO might just be what the naturopathic doctor ordered.

In health and happiness,

Dr. Preet Khangura, ND


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