SIBO part 2: Open Wide…..say ahhhh
27 August 2019
A popular theory of the pathophysiology of small intestinal bacterial overgrowth (SIBO) is that it’s caused by bacteria in the colon moving up into the small intestine due to a faulty ileocecal valve (a valve that separates the distal (last) section of the small intestine, the ileum with the colon). As you can see, in this image that’s quite some journey.
A new study on one section of the small intestine, the jejunum, challenges that concept. The study—which used polymerised chain reaction (PCR) to look at bacterial genomes—found that the jejunum has its own unique microbiota, much more akin the oral microbiome and that there wasn’t much similarity between the organisms and PCR data in the jejunum compared to the colon at all.
The conclusion was that the jejunum contains a distinctive bacteria population of facultative anaerobes and oxygen-tolerant obligate anaerobes, similar to those found in the oral cavity. And where there’s been a teaching in the past that somehow retrograde flow from the colon goes up into the jejunum. This concept was challenged quite powerfully last year at the SIBO Con and this year also by gastroenterologist Dr. Richard McCallum, MD
As a practitioner that takes a specialist interest in Gut health, this makes a great deal of sense to me, that we consider the oral microbiombe far more.
The human microbiome begins in the mouth and continues through until the anus, and an imbalance in your gut bacteria “community” is known as dysbiosis. As practitioners we have spent so much time on the gut, and now we are giving the oral microbiome it’s time in the limelight too.
A dysbiosis of the 'community' in the mouth is most commonly as a result of gingival crevices, the small gaps between your teeth and gums. Oral microbiota just love to live in these little cosy pockets forming “plaque”. The bacteria use the plaque to protect themselves and they are in close contact with your immune system via the gum’s blood vessels.
When you’re healthy, your good bacteria are diverse and balanced. Friendly oral flora is present, working in tandem with your immune system. Probiotic bacteria compete with harmful bugs, preventing overgrowth and disease.
But when bacterial imbalance occurs in pockets, inflammation can occur - and the scene is set!!!
Now, this makes much more sense to me than a retrograde back flow, that also has to travel against gravity. The jejunum lies between the duodenum and the ileum. In adult humans, the small intestine is usually 6-7m long, about two-fifths of which (2.5 m) is the jejunum, thus that’s a 4-meter journey of potential retrograde back flow from the ileocecal valve to the jejunum!
Of course, this doesn’t just relate to SIBO, oral health is vitally important to our general health, with well-established links to cardiovascular disease, diabetes, weight gain and weight loss resistance and many other conditions – as well as to people's quality of life. In terms of weight loss resistance and weight gain, the link is via LPS laden bacteria. LPS are large molecules that are found in the outer membrane of Gram-negative bacteria, and elicit strong immune responses and thus inflammation.
Cani and associates (2008) found that bacterial lipopolysaccharide (LPS) levels set the tone of insulin sensitivity and the onset of obesity and diabetes. An increased gut permeability and poor gum health allows for the passage of LPS through the gut or oral barrier into the systemic circulation.
Tips to Keep Your Oral Flora and Good Mouth Bacteria in Balance
If you work with a practitioner, are a client of mine or are attending my What’s Your Gut Feeling Functional Day Retreat this test is available to you.
As always - in health, Tanya x