SIBO MYTHS DEBUNKED

What You Really Need to Know About Small Intestinal Bacterial Overgrowth

If you’re experiencing daily bloating, gas, abdominal pain, or unpredictable bowel habits, you’re not alone—and it’s not "just IBS."

One increasingly recognized cause of digestive distress is Small Intestinal Bacterial Overgrowth (SIBO), a condition where excessive or misplaced bacteria colonize the small intestine. This overgrowth disrupts normal digestion and absorption, often mimicking or overlapping with other gut disorders like IBS, acid reflux, or food sensitivities.

But with the rise in popularity of the term “SIBO” has come an increase in myths and misinformation. Let’s separate fact from fiction—using current evidence-based data—so you can better understand what’s happening in your gut and how to begin your journey toward lasting relief.

Myth 1: SIBO Is Rare

Truth: It’s more common than most people realize, especially in those diagnosed with IBS.

A meta-analysis published in Gut and Liver found that up to 78% of IBS patients tested positive for SIBO using hydrogen and methane breath tests (1). Many people living with "IBS" may be managing symptoms without addressing the root cause.

In my Toronto practice, I regularly see patients who have struggled with digestive symptoms and on and off various diets for years before discovering they were dealing with undiagnosed SIBO.

Myth 2: SIBO Is an Infection Caused by “Bad Bacteria.”

Truth: It’s not about what bacteria are present—it’s about where they are.

The small intestine typically contains relatively few microbes compared to the colon. In SIBO, the bacteria are often normal commensals that have migrated from the large intestine to the small intestine, where they ferment carbohydrates too early in the digestive process. This fermentation produces gases like hydrogen, methane, or hydrogen sulphide, which cause bloating, distension, and altered bowel movements.

That’s why simply killing bacteria with antibiotics or herbal antimicrobials is often not enough. The underlying issue is a breakdown in the body’s gut defence mechanisms.

Myth 3: Antibiotics or Diet Alone Will Cure SIBO

Truth: While prescription antibiotics (like rifaximin) or herbal antimicrobials (such as berberine, neem, or oregano oil) can reduce bacterial load, long-term resolution requires a comprehensive, individualized strategy.

Evidence suggests that recurrence rates of SIBO are high (up to 45% within 9 months [2]), especially if underlying causes aren't addressed.

An effective treatment plan typically includes:

• Biofilm disruptors to weaken bacterial resistance

• Motility agents to improve intestinal clearance (MMC support)

• Digestive support (enzymes, bile acids, stomach acid)

• Dietary guidance (such as low-FODMAP, SIBO-specific diets)

• Stress and nervous system support

• Careful use of probiotics (often spore-based or yeast-derived)

Myth 4: Everyone with SIBO Should Take Probiotics

Truth: Not all probiotics are helpful in SIBO, and some can make symptoms worse.

While certain strains of probiotics have been shown to improve SIBO treatment and recurrence, some studies suggest that traditional lactobacillus-based probiotics can exacerbate symptoms in some cases (3). That’s because these strains may further contribute to fermentation in an already overpopulated small intestine.

In contrast, Bacillus Coagulans (and/or other soil-based probiotics) or Saccharomyces boulardii (a beneficial yeast) may provide symptom relief in select cases without contributing to overgrowth.

Myth 5: SIBO Happens Without a Reason

Truth: SIBO is a symptom of an underlying dysfunction in the gastrointestinal system.

To truly resolve and prevent recurrence, we must uncover what created the environment for overgrowth in the first place. Contributing factors can include:

• Low stomach acid or pancreatic enzyme insufficiency

• Impaired motility, especially the Migrating Motor Complex (MMC)

• Bile insufficiency or gallbladder dysfunction

• Structural issues (e.g., adhesions or ileocecal valve dysfunction)

• Nerve or vagus dysfunction

• Chronic stress

• History of food poisoning, antibiotic use, or abdominal surgery

This is where functional digestive testing (including breath testing and stool analysis) can guide targeted, root-cause interventions.

Healing SIBO: An Individualized Approach

In my practice, not only do I offer SIBO breath testing (including both hydrogen and methane gas analysis) and treatment, but a fully individualized treatment approach that considers the why, not just the what. Stool testing and other diagnostics are also always considered as part of the assessment, as many other concerns like hydrogen sulphide bacteria and visceral hypersensitivity can also mirror SIBO.

If you're tired of living with bloating, discomfort, and unreliable digestion, there is a path forward. With the right testing, personalized protocols, and holistic support, SIBO can be effectively managed and often resolved.

Ready to get to the root of your symptoms and feel like yourself again?

Book a personalized consultation with Dr. Courtney Holmberg, ND — a leading Naturopathic Doctor in Toronto with a clinical focus on gut and hormonal health.

📅 Schedule your appointment online or call (647) 351-7282 to get started today.

References:

• Tansel A, Levinthal DJ. Understanding Our Tests: Hydrogen-Methane Breath Testing to Diagnose Small Intestinal Bacterial Overgrowth. Clin Transl Gastroenterol. 2023 Apr 1;14(4):e00567. doi: 10.14309/ctg.0000000000000567. PMID: 36744854; PMCID: PMC10132719.
  

• •Lauritano, Ernesto C. M.D.1; Gabrielli, Maurizio Ph.D.1; Scarpellini, Emidio M.D.1; Lupascu, Andrea M.D.1; Novi, Marialuisa M.D.1; Sottili, Sandra Ph.D.2; Vitale, Giovanna M.D.1; Cesario, Valentina M.D.1; Serricchio, Michele M.D.1; Cammarota, Giovanni M.D.1; Gasbarrini, Giovanni M.D.1; Gasbarrini, Antonio M.D.1. Small Intestinal Bacterial Overgrowth Recurrence After Antibiotic Therapy. American Journal of Gastroenterology 103(8): p 2031-2035, August 2008.

  
  

• Chen WC, Quigley EM. Probiotics, prebiotics & synbiotics in small intestinal bacterial overgrowth: opening up a new therapeutic horizon! Indian J Med Res. 2014 Nov;140(5):582-4. PMID: 25579137; PMCID: PMC4311309.