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SIBO – The Major Cause Of Irritable Bowel Syndrome And Histamine Intolerance

  • Writer: Brainz Magazine
    Brainz Magazine
  • Sep 25, 2022
  • 5 min read

Updated: Sep 26, 2022

Written by: Joanne Kennedy, Executive Contributor

Executive Contributors at Brainz Magazine are handpicked and invited to contribute because of their knowledge and valuable insight within their area of expertise.

“SIBO CAUSES 60-80% OF IBS CASES WORLDWIDE” Do healthy foods, including garlic, mushrooms, apples, pears, and yogurt, cause unwanted gastrointestinal symptoms – belching, heartburn, bloating, and/or abdominal pain? Do you feel tired after eating, experience brain fog, and/or have restless legs? Have you experienced adverse reactions to probiotics, fermented foods, and bone broths? If yes, then you may have SIBO. In fact, studies show that up to 80% of Irritable Bowel Syndrome cases worldwide are caused by SIBO. So, what is SIBO and how is it affecting your health?

SIBO word cloud on a digital tablet, flat lay with a cup of coffee.

SIBO stands for Small Intestinal Bacterial Overgrowth.


SIBO occurs when there is an abnormal number or type of bacteria present in the small intestine. SIBO bacteria take starches and fibres from FODMAP foods (including those mentioned above) and ferment them into gases ‒ hydrogen, methane, or hydrogen sulfide. These gases damage the small intestine causing gastrointestinal symptoms. Furthermore, damage and inflammation resulting from SIBO can cause a cascade of problems, including:

  • Impaired nutrient absorption: inflammation causes changes in mucosal epithelial cells at the predominant nutrient absorption sites resulting in impaired nutrient absorption. Common nutrient deficiencies include Vitamin B12, thiamine (B1), nicotinamide (B3), iron, magnesium folate, and iodine.

  • Fat malabsorption: SIBO bacteria deconjugate (break apart) bile acids. The bile acids aid in the absorption of lipids (fats). Fat malabsorption can lead to deficiencies in fat-soluble vitamins A, D, E, and K.

  • Intestinal hyperpermeability (leaky gut): allows toxins, histamines, and food particles to cross into blood circulation, activating an immune response in the body that may lead to food intolerances and/or allergies and skin conditions.

  • Histamine intolerance: SIBO is a major cause of histamine intolerance as the resulting inflammation increases histamine levels in the body. Signs and symptoms of histamine intolerance include eczema, acne, hives, chronic reflux, headaches, migraines, vertigo, anxiety and insomnia.

SIBO and Histmanie Intolerance


Histamine intolerance occurs when the accumulation of histamine is beyond the body’s capacity to break it down and excrete it. SIBO has a 4-fold effect on histamine levels in the body.


1. Inhibits DAO enzyme: the DAO enzyme breaks down histamine in the gut. Inflammation impairs the function of this enzyme, preventing the breakdown and excretion of histamine.


2. Intestinal hyperpermeability: triggers an inflammatory response from the immune system that releases histamine from cells.

3. Large bowel dysbiosis (imbalance of good to bad bacteria in the large bowel): can lead to an increase of histamine-producing bacteria that require the DAO enzyme for breakdown.


4. Nutrient deficiencies: the enzyme that breaks down histamine in the central nervous system (Histamine-N-Methyl-Transferase enzyme) requires Vitamin 12, zinc, and folate to function optimally. SIBO can cause a deficiency in these nutrients.


Symptoms of SIBO

  • Gastrointestinal symptoms: bloating, belching, flatulence, abdominal pain, nausea, constipation and/or diarrhea, nutrient deficiencies (particularly iron, B12, zinc), weight loss, fat malabsorption.

  • Systemic symptoms: brain fog, fatigue, weakness, joint pain, fibromyalgia, interstitial cystitis, restless legs.

  • Histamine Symptoms: headaches, migraines, bladder irritation, anxiety, heart palpitations, vertigo, insomnia, PMS, PMDD, worsening of peri-menopause symptoms, skin issues including eczema, hives, acne and rosacea.

Other clues pointing to SIBO

  • Prebiotics/probiotics make your symptoms worse

  • Symptoms temporarily improve on antibiotic therapy

  • Symptom onset after food poisoning – immediately or months later

  • Fibre makes constipation worse

  • Xylitol and sugar alcohols exacerbate symptoms

  • Celiac patients whose symptoms persist whilst on a gluten-free diet

Causes of SIBO

  • Structural: obstruction, migrating motor complex damage, ileocecal valve dysfunction.

  • Surgery/injury: abdominal surgery, brain/spinal trauma – including whiplash, fistula, abdominal adhesions, endometriosis.

  • Medications/drugs: Excessive use of antibiotics, excessive use of proton pump inhibitors, alcohol.

  • Environmental: stress, mould illness

  • Disease/disorders: food poisoning, Helicobacter pylori infection, hypochloridria, endometriosis, celiac disease, Crohn’s disease, gastroparesis, diabetes, liver disease, poor bile flow, pancreatic enzyme insufficiency.

  • Migrating motor complex (MMC). The MMC Is a system of electrical waves that pulse through the small intestine propelling contents from the stomach to the end of the small intestine, cleansing the small intestine of remaining food and bacteria from a recent meal. Importantly, it’s only active in the fasting state – between meals and overnight.

MMC deficiency causes SIBO as it limits bacterial clearance, while lack of pulses leads to stagnation in the small intestine and, like a swamp, creates a perfect breeding ground for bacterial growth.


Stress, food poisoning, constant snacking, disease (hypothyroid, diabetes, Lyme’s), injury (brain/spinal, whiplash), and drugs (opiates, smooth muscle relaxants) have potential to cause MMC deficiency


SIBO Testing


SIBO testing is used to determine the type of SIBO. My clinic uses a non-invasive lactulose breath test for hydrogen or methane SIBO. The test is completed at home, requiring a preparation diet one day prior to testing and an overnight fast before waking to take a series of 6 breath tests over 3 hours.


Hydrogen sulfide SIBO


There is currently no available test in Australia to detect Hydrogen sulfide SIBO. An experienced practitioner, however, can ascertain levels of hydrogen and methane along with any adverse reactions to a low FODMAP if there is Hydrogen sulfide SIBO.


Retesting


Resting your SIBO levels after treatment (natural or allopathic) is important! Clinically we have found retesting reduces ‘SIBO relapse.’ This is because from retesting, we can determine the efficacy of treatment and if it is time to reintroduce FODMAPs foods.


SIBO Treatment


SIBO treatment involves:

  • Eradication of the bacterial overgrowth via a low FODMAP/low resistant starch diet and a supplementation protocol pertinent to the SIBO type.

  • Addressing the symptoms and complications of SIBO, including nutritional deficiencies.

  • Reducing histamine levels. If you are exhibiting signs and symptoms of histamine intolerance, it’s important to get histamine levels down, not only to relieve histamine symptoms but to allow the body to break down histamine caused by SIBO.

  • Determine/address underlying causes ‒ a fundamental principle of natural medicine. In identifying and treating the individual causes of SIBO the potential for SIBO relapse is greatly minimised.

Due to the nature of SIBO, it’s recommended to work with a practitioner experienced in SIBO and the small intestine as treatment is often contradictory to standard gut protocols that often focuses on the large bowel. Furthermore, an experienced practitioner will not only guide you in treatment but will help determine the cause. Addressing the cause will give the best chance of avoiding relapse.


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Joanne Kennedy, Executive Contributor Brainz Magazine

Joanne Kennedy is a Naturopath and specialist in methylation, histamine intolerance, gut health, and women’s hormones. Joanne runs a successful clinical practice in Sydney, Australia and sees patients online worldwide. Joanne’s approach is to identify the root cause of illness. This is done by the use of functional pathology testing, assessing the biochemical individuality of each patient, assessing environmental exposures, as well as individual genetic testing if required.

 
 

This article is published in collaboration with Brainz Magazine’s network of global experts, carefully selected to share real, valuable insights.

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