Small Intestinal Bacterial Overgrowth
the most common cause of IBS symptoms
What is SIBO?
Small intestinal bacterial overgrowth (SIBO) occurs when an abnormal amount of bacteria (mostly from your own microbiome) overgrow in the small intestine, causing increased fermentation and symptoms of gas, bloating, dyspepsia, constipation or diarrhea. This condition is testable and treatable.
Over the last three decades, there has been growing recognition of the role of gut bacteria in the health of the gastrointestinal tract. It has been found that anywhere between 17 - 85% of cases of irritable bowel disease may in fact be attributed to an underlying overgrowth of bacteria into the small intestines, called SIBO (small intestinal bacterial overgrowth). It is important to note that this is NOT an infection, but an overpopulation of bacteria in a location not meant for such high concentrations.
​
If you’re struggling with bloating after meals, irregular stools, or chronic abdominal discomfort, SIBO might be an underlying cause— it’s more common than you think.
Common SIBO Symptoms Include:
- gas (belching or flatulence) & bloating , especially after eating
- stomach pain
- diarrhea, constipation, or both
- reflux or nausea
- fatigue
- in extreme cases, weight loss
The small intestine's role is primarily that of nutrient absorption, and therefore overgrowth in this area allows the bacteria to rob you of essential nutrients. Vitamin D, K, iron and B12 deficiencies are popular among these patients.
The inflammation produced by the endotoxins of the bacteria is also an attributing cause of leaky gut syndrome and the development of multiple food sensitivities. Furthermore, SIBO can inhibit nutrient absorption and lead to carbohydrate intolerance, malabsorption/malnutrition, anemia, weight loss, and so on. Bacterial imbalances can also change the way hormones are metabolized and excreted and have been correlated with acne, irregular periods, and other hormonal issues like adrenal fatigue.
Patients with gastrointestinal distress may benefit from SIBO testing, especially those with a history of chronic constipation, diarrhea, weak stomach acid, or generalized maldigestion. Successful eradication of SIBO has been shown to significantly reduce bloating, gas, diarrhea, and abdominal pain in patients.
What causes SIBO?
While we don't know the cause for certain, it suspected that SIBO can develop for several reasons:
-
Impaired gut motility (post-surgery, hypothyroidism, or stress)
-
Long-term PPI or antibiotic use
-
Underlying conditions like IBS, IBD, or endometriosis
-
Adhesions or anatomical issues in the small bowel
SIBO Breath Testing
Gold Standard for diagnosing SIBO involves a Lactulose Breath Test, where a lactulose substance is administered after 24 hours of a non-fermentable diet. Breath samples are assessed every 20 mins for 3 hours following administration of the substance, and hydrogen/methane gas is measured in each sample. A steep rise or overall elevation of either of these gases indicates that bacteria are fermenting the sugar, and is deemed positive for SIBO.
SIBO Treatment
My approach focuses on identifying and treating the root cause of your SIBO using a 3-step method:
-
Reduce bacterial overgrowth – using antimicrobial herbs or medications.
-
Restore healthy motility & digestion – with lifestyle changes and supportive supplements.
-
Prevent recurrence – by addressing contributing factors like diet, stress, and gut-brain communication.
Treatment is always personalized based on your test results, symptoms, and overall health picture.
Remember... the bacterial strains in our guts are not just a bunch of individual organisms, but a collection of organisms that
operate as an ecosystem
You can't cut down the rainforest and expect it to regrow in a day. ​ Probiotics have been shown to only repopulate the gut for up to 21 days following discontinuation, so ensuring the survival of the original beneficial organisms is essential. Furthermore, while Specific Carbohydrate/FODMAPs diets have been shown to be helpful for management of symptoms, one must remember the problem lies not in the food itself, but in what your ecosystem is doing to the food, and therefore diets should never be the long-term solution.
If your stuck on using diet to manage your symptoms, you likely haven't corrected the problem.​
The key approach that differentiates our focus in treating SIBO in comparison to others is our focus on maintaining the beneficial bacteria during treatment, and remission of symptoms long term. Emphasis is placed on saving butyrate, propionate, and acetate-producing beneficial bacteria (lactobacillus and bifido bacterial strains), all while eradicating bacterial overgrowth. ​
Once the terrain is reset and repopulated, associated conditions that may have been attributing to symptoms are then addressed, all while ensuring chance of recurrence is minimized.
The goal of treatment is to address the underlying overgrowth and resolve symptoms for good.
suspect this might be you?
let's explore the possible connection to your symptoms
Dr. Courtney Holmberg, ND is located in downtown Toronto, and works with patients across the GTA (and virtually around Ontario) who are seeking proper testing, and are looking for natural, comprehensive solutions to gut health. Whether you're newly diagnosed, looking for testing, or are experiencing relapsing symptoms, we are here to help!
