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Is SIBO driving your IBS?

SIBO stands for Small Intestinal Bacterial Overgrowth. As its name suggests, SIBO occurs when bacteria begin to overgrow in the small intestine - Specifically, when bacteria translocate from the large intestine (the home of our microbiome) to the small intestine, which is meant to be relatively sterile.

It’s important to understand that the small intestine is where digestion and absorption take place; When bacteria begin to populate there, they can interfere with these processes and generate symptoms that mimic IBS (gas, extreme bloating, irregular bowels, etc). In fact, research suggests that SIBO may be involved in up to half of all IBS cases, with one study showing as high as 84%. This same study also showed that eradicating SIBO led to a 75% improvement in IBS symptoms - Yep, you heard me right!


Here's what's happening:


When bacteria are present in the small intestine, they feed off of fermentable carbohydrates, also known as FODMAPs. In doing so, they produce gaseous bi-products in the form of Hydrogen, Methane and/or Hydrogen Sulfide. These gasses perpetuate the IBS-symptoms commonly seen with SIBO.


Most commonly, methane gas is associated with IBS-C (constipation), while Hydrogen gas is associated with IBS-D (Diarrhea). However, it is not uncommon to see both of these gasses produced simultaneously.


How do you develop SIBO? Common Root Causes:

There are many mechanisms by which SIBO can occur, and it is absolutely crucial to determine the root cause of your overgrowth in order to prevent a relapse. The pre-disposing factors for Sibo fall under 3 main umbrellas:


#1) Weakened Digestion

Low stomach acid (HCL) is at the root of many Sibo cases in that it acts as a Gate Keeper for the rest of the digestive system. Specifically, adequate levels of stomach acid are needed in order to stimulate the rest of the digestive processes - HCL signals the gall bladder to release Bile, and signals the pancreas to release digestive enzymes. Stomach acid also helps to stimulate peristalsis: the wave of movement that sweeps food from one end of the digestive tract to the other.


When food is not efficiently digested or propelled through the digestive tract, it “hangs around” for too long, which gives bacteria a better chance to feed off of it and over grow.

Stomach acid is also the first line of defence against pathogenic organisms that may be present in our food. When it is not sufficiently present, pathogens won't be neutralized and can subsequently wreak havoc on the gut and the digestive system.


Chronic stress is another big one here, as a constant state of “fight or flight” means digestion is permanently put on the back burner.

#2) Impaired Motility of the Migrating Motor Complex

Within the digestive tract we have a mechanism called the Migrating Motor Complex (MMC), which functions like a broom to clean up and sweep bacteria from the small to the large colon. When the MMC is malfunctioning for any reason, bacteria won’t be swept out of the small intestine and this can lead to an overgrowth.


A few factors than can inhibit the Migrating Motor complex from functioning properly include:

  • Constant snacking, grazing and improperly spacing meals: The MMC is stimulated by hunger, so constant snacking never gives it a chance to do its job.

  • A recent episode of Food poisoning

  • Traumatic brain injuries, spinal cord injuries or concussions

  • Hypothyroidism: A sluggish thyroid slows down everything in the body, including the migrating motor complex

  • Chronic laxative use or chronic colon hydrotherapy

#3) Impaired Flow in the Digestive Tract


Impaired flow means that bacteria cannot be properly cleared from the small intestine. This is often rooted in a blockage in the digestive tract (often due to tissue strictures / adhesions after a surgical procedure) or a malfunctioning ileocecal valve, which is meant to be a one-way gate keeper between the small and large colon. When the Ileocecal valve is damaged, bacteria are able to translocate from the large to the small intestine.


Certain medications can also contribute to SIBO, including long-term PPI’s, anti-spasmatic medications, birth control pills, thyroid medications and opiates.


What signs should I be looking for? Common Symptoms of SIBO:

Sibo is often described as more of a Syndrome, in that no-single symptom is “definitive” of the condition. Instead, Sibo often presents as a collection of multiple symptoms simultaneously, many of which are non-digestive, including:

  • Heartburn

  • Irregular bowels: Chronic Constipation, Diarrhea or a combination of the two

  • Stomach cramping

  • Chronic bloating and abdominal distension, often described as “looking 6 months pregnant”

  • Flatulence, often smelling like Sulfur

  • Skin issues: Rashes, Eczema, Dermatitis

  • Halitosis (severe bad breath)

  • Joint pain

  • Anxiety

  • Fatigue

  • Headaches

A few additional indicators that Sibo may be present include:

  • Symptoms worsening after eating fiber-rich foods (or fiberous foods causing constipation)

  • Symptoms worsening after eating foods that are fermented (sauerkraut, kimchi, miso, pickles, etc.)

  • A mildly tender palpable mass in the right lower quadrant of the abdomen (around the Ileocecal Valve)

  • Redness on the outside of the abdomen

  • Aggravation of symptoms after taking a probiotic supplement, especially one that contains Fructo-Oligosaccharidse (FOS)

There are also many conditions that can occur concurrently with SIBO, including:

  • GERD

  • Leaky Gut

  • Fat malabsorption, stearrorhea or a deficiency in fat-soluble vitamins (ADEK)

  • Fibromyalgia

  • Nutrient deficiencies, especially Iron and B12

  • Skin conditions: Eczema, Psoriasis, Rosacea and Acne

  • Endometriosis


How do I know for sure if I have SIBO? Test, don't guess.


The gold standard (and the most popular option) when it comes to testing for SIBO is a Glucose or Lactulose Breath Test. This involves consuming a substrate containing either glucose or lactulose, and then breathing into a series of tubes to measure the levels of methane and hydrogen gas in your breath. The idea is that if bacteria are present, they will feed off of the substrate and release either methane and/or hydrogen gas. These gasses can then be measured to determine the presence and severity of an overgrowth. Other options for testing include comprehensive stool analyses like the GI Map test, or completing an Endoscopy.


What to do? Treating SIBO:


Eradicating SIBO typically involves some form of dietary intervention in combination with anti-microbial herbs and/or prescription antibiotics (Rifaximin and/or Nystatin).


The diets most commonly indicated for SIBO include the Low Fodmap diet, the Specific Carbohydrate Diet or the GAPS diet. There are also some Sibo-specific diets available such as the Bi-Phase Diet by Dr. Nirala Jacobi.


The antimicrobials most commonly used for SIBO include neem, berberine, oil of oregano, allicin, goldenseal, oregan grape and grapefruit seed extract. Your practitioner will help you decipher which blend is the most appropriate for your particular case.


Remember, IBS isn't a life sentence. If you are struggling with any of the symptoms listed above, click here to schedule a free discovery call or read more about Gut Rehab, so that we can work together to finally get to the bottom of your IBS!



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