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SIBO (Small Intestinal Bacterial Overgrowth) is the presence of excessive amounts of bacteria within the small intestine.

Though previously thought to only impact a small number of individuals, SIBO has been found to occur at a much higher rate — especially in older populations.

Symptoms range from mild to chronic. Chronic symptoms are unique to each individual, but may include bloating, burping, reflux, constipation diarrhea, weight loss, nutritional deficiencies, and carbohydrate malabsorption.

If you suffer from SIBO, many natural options can help you find relief.

What Causes SIBO?

SIBO occurs when the bacteria inside the large intestine migrate to the small intestine where they interfere with normal digestive function.

Normally, the small intestine has only a small population of bacteria.

Several risk factors influence the development of SIBO, including but not limited to:

  • Impaired stomach acid production or PPI/antacid use
  • Poor bile production or flow
  • Poor pancreatic enzyme function
  • Impaired gut motility
  • Low secretion of IgA
  • Older age
  • Other medications such as narcotics and opiates such as codeine

(Hawrelak, 2015)

The lack of stomach acid is an issue because it has antimicrobial properties — it's responsible for breaking down protein from food. A lack of stomach acid can lead to higher levels of bacteria and undigested protein, which can lead to putrefaction and poor digestion.

Impaired gut motility also takes its toll. Though stomach acid and enzymes help break down food, our gut needs help from our nerves and muscles to further digest food and move it through the body.

When motility is impaired, bacteria are more likely to ferment slow-moving food and residue. This promotes the growth of even more bacteria, creating a vicious cycle.

Other contributing risk factors associated with SIBO include:

The presence of comorbidities

Particularly those that further impair the motility of the stomach and small intestine. Examples of such diseases are:

Metabolic Disorders

  • Diabetes
  • Hypochlorhydria

Structural or anatomical defects

  • Bowel obstruction
  • Fistulas
  • Adhesions
  • Strictures
  • Small bowel syndrome


  • Weight loss surgery — Particularly procedures that alter the small intestines structure
  • Other surgery — Such as a colectomy, which impairs the ileocecal valve and allows colonic bacteria to flow back up into the small intestine. (Roland et al., 2014)


  • Opiates
  • Proton pump inhibitors (PPIs)
  • Antibiotics
  • Antispasmodics


Trauma can damage nerves or muscles, resulting in intestinal neuropathy.


Individuals 60 and older are at higher risk for SIBO.

Symptoms and Diagnosis

Symptoms of SIBO differ from person to person. They can range from mild to severe and can become chronic if not dealt with effectively. Symptoms are almost identical to IBS symptoms, yet not everyone with IBS has SIBO.

The amount of gas and toxins that these microorganisms produce can be tough on the body. These gases are what produce milder symptoms such as bloating, gas, and flatulence. (Posserud et al., 2007)

Other symptoms may vary depending upon which bacteria are present within the small intestine. Some of these symptoms are:

  • Abdominal pain
  • Nausea
  • Chronic constipation
  • Chronic diarrhea
  • Fatigue
  • Weakness
  • Weight loss
  • Abdominal distension
  • Fecal incontinence

Diagnosing SIBO is conducted with a variety of tests such as:

  • Breath test — The most accessible and affordable test, though it can produce false negatives and positives.
  • Endoscopy with aspiration — Invasive and more expensive, but the results are more accurate
  • Organic acid test — A urine test that looks for malabsorption, deficiencies, yeast, and bacteria overgrowth. This test is not a direct measure of SIBO.
  • Comprehensive stool analysis — Examines the level of good and bad bacteria in the stool. Elevations of bacteria found on this test may be associated with SIBO. However, this test is not the best practice for SIBO diagnosis.

Treatments Options

Antibiotics are a mainstream, quick way to treat SIBO. However, antibiotics can come with a list of nasty side effects. There is also a high rate of relapse because antibiotics do not address the underlying causes of the SIBO.

Your treatment goal should not be to combat SIBO and its symptoms solely. It should also be to create a long-term solution, so you don't have to worry about a relapse. The best way to do that is with a holistic treatment approach

Natural antibiotics

  • Oil of oregano — A strong general antimicrobial, this is suitable for short periods
  • Standardized Allicin Extract from garlic — Has potent antibiotic, antiviral, anti-fungal, and antimicrobial properties.
  • Berberine-containing herbs such as Phellodendron and Barberry — These herbs assist with removing endotoxins produced by bacteria.
  • Pomegranate husk tincture — A gentle yet effective antimicrobial that causes no harm to the microbiome.

GAPS Diet (Gut and Psychology Syndrome Diet)

GAPS is a diet that heals the gut while starving harmful bacteria and overgrowth. In the GAPS diet, you eliminate all grains, starchy vegetables, sugar, beans, and legumes. Common allergens such as dairy and eggs are initially prohibited, as well. However, they can be reintroduced later on.

Other diets used for SIBO include the Bi-Phasic Diet from Nirala Jacobi, Fast Tract Diet from Norm Robillard, and the low FODMAP diet. The best diet is the one that works specifically for you.

Digestive enzymes and hydrochloric acid

Aids in the proper digestion of food.

Here's a digestive enzyme product we like.

Amino acids and antioxidants

  • L-glutamine
  • N-Acetyl Glucosamine
  • Deglycyrrhizinated licorice (DGL)
  • Quercetin

Here's a reputable L-glutamine product from Amazon.

Probiotic supplementation

Many probiotic strains can reduce methane gas levels, improve motility, and repair gut lining.

You can check out Pure's Probiotics G.I.

Vitamin supplementation

Consult your healthcare practitioner and find out which deficiencies are present — then supplement accordingly.

Most common deficiencies found in individuals with SIBO are:

  • Vitamin B12
  • Vitamin D
  • Calcium
  • Iron
  • Magnesium
  • Zinc

Here's a reputable Zinc product.

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Research Citations

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