Your guide to Small Intestinal Bacterial Overgrowth or SIBO

Updated: Jul 18, 2020

Closely associated with irritable bowel syndrome, SIBO or small intestinal bacterial overgrowth is exactly that, an overgrowth of microorganisms that normally reside in the lower part of the gut (colon). Symptoms can be debilitating and unfortunately recurrence is common but anyone with gut issues, food sensitivities, autoimmune disorders and malabsorption symptoms (eg anemia) should be assessed for SIBO. Here's an important summary of this potentially devastating condition.

What are the symptoms and key indicators of SIBO?

Irritable bowel symptoms such a....

  • Bloating and gas

  • Belching and flatulence

  • Abdominal pain and/ or cramps

  • Diarrhea or constipation on both

Other symptoms include:

  • Heartburn

  • Nausea

  • Food senstivities

  • Headaches

  • Joint pain

  • Respiratory Symptoms

  • Skin reactions

  • Malabsorption symptoms eg. anemia, steatorrhea

  • Brain symptoms such as brain fog, poor memory, depression/anxiety

  • Note: Systemic symptoms are due to hyper-permeability of the gut causing malabsorption, toxin release into the blood stream and an inflammatory and immune response.

Key indicators include:

  • A dramatic but short term improvement in IBS or gut symptoms after a course of antibiotics.

  • Chronic gut symptoms occurring after a long term course of broad spectrum anti-biotics (eg. amoxicillin, penicillin, erythromycin, doxycycline, ciprofloxacin or norfloxacin).

  • Worsening of GI symptoms from probiotic use or consuming fermented foods.

  • Worsening of symptoms when increase fibre or take prebiotics (as food for commensal bacteria).

  • When someone with coeliac disease reports insufficient improvement from a strict gluten-free diet.

  • Development of chronic gut symptoms after taking protein pump inhibitors (usually used for reflux & heart burn eg. losec or omeprazole) or after taking opiates (eg. oxycodon, heroin, morphine, methadone, codeine and pethidine).

  • Chronic low iron or ferritin levels with no other cause.

  • Chronic gut symptoms after a bout of viral gastroenteritis or bacterial food poisoning (post-infectious IBS).

What disease and disorders are associated with SIBO?

  • Irritable Bowel Syndrome (IBS)

  • Inflammatory Bowel Disease (IBD)

  • Gastro-esophageal relfux (GERD)

  • Celiac and gluten sensitivity

  • Autism

  • Fibromyalgia

  • Acne rosacea

  • Diverticulitis

  • Interstitial cystitis

  • Restless legs syndrome

  • Diabetes

  • Hypothyroidism

  • Scleroderma

  • Cirrhosis & hepatic encephalopathy

So what increases your likelihood of SIBO?

  • Poor gut motility and altered bowel flow is thought to be the main factor. This can be due to a number of reasons but examples include adhesions and scar tissue from previous abdominal surgery or from endometriosis, or poor ileocecal valve function.

  • Use of proton pump inhibitors (eg.losec/omeprazole), opiates (eg. codeine, oxycodon) or broad spectrum antibiotics (eg. amoxicillin, penicillin, erythromycin, doxycycline, ciprofloxacin or norfloxacin).

  • High stress lifestyle

  • Low levels of digestive enzymes

  • Chronic inflammation and immune dysfunction

  • History of food poisoning or gastroenteritis

  • Autoimmune disorders that destroy nerve cells

  • Diabetes

How is SIBO diagnosed?

SIBO is commonly diagnosed from your health history and/or a SIBO Breath Test.

The micro-organisms in your gut produce hydrogen and methane. They are not made by the human body itself but by the microflora within your gut. (There are about 10 times as many microbial cells in the human body as there are human cells). In fact, bloating after meals is directly related to the production of gas by these micro-organisms.

The SIBO breath test measures the hydrogen and methane gas produced by organisms in the small intestine that has diffused into the blood, then the lungs for expiration. They are graphed over a 2-3 hour period and then compared to a baseline.

The test involves having to be on a special (little to no carbohydrate) diet for 1-2 days prior to the test. A baseline is taken just prior to consuming a sugary solution of glucose or lactulose. Then every 20 minutes for 2-3 hours the methane and hydrogen levels are measured.

An accurate test requires you to adhere to the preparatory diet. Plus, it is best to be off any antibiotics or anti-microbial herbs for at least 2 weeks prior. You should also not take any protein pump inhibitors, laxatives, high dose magnesium or vitamin C for 2-3 days prior.

If you wish to have a SIBO breath test please contact a naturopath or functional medicine health professional (like myself). GPs are slowly becoming more aware of this condition and may be able to help also. The cost for this test is around $250-300 NZD.

How do you treat SIBO?

Antibiotics or Herbal anti-microbials - A specific antibiotic called Rifaximin (brand name Xifaxan) can be used to treat SIBO. How much and with what depends on the type of SIBO - methane or hydrogen predominant or both.

Some herbal anti-microbials include berberine, peppermint & oregano oil , Neem (Azadirachta inidca), allicin from garlic, and Candibactin by Metagenics.

Diet - since the bacteria primarily eat carbohydrates all SIBO diets aim to reduce carbohydrates and therefore their food supply. For more info on the diets please go to Dr Siebecker's website. The diet will help reduce symptoms but doesn't really get rid of the excess bacterial organisms. Treatment with diet only may be enough for babies and young kids but ideally an anti-microbial would also be used.

SIBO commonly recurs and treating is not always an easy process.

I'd highly recommend seeking help from a health professional, especially when trying to address any microbial overgrowth or infection. There are however a few things you can do to help prevent a small intestinal bacterial overgrowth or a recurrence.

How to prevent SIBO or a recurrence

Improve digestive juices and make sure you have adequate hydrochloric acid production

To do this you need to first address any reason for low stomach acid (hydrochloric acid - HCl). HCl activates pepsinogen into the enzyme pepsin. Pepsin helps digest proteins.

  • Reduce stress. Hydrochloric acid secretion may be completely inhibited by stress, emotion, or worry.

  • Sit to eat and thoroughly chew your food.

  • Avoid antacids and protein pump inhibitors (eg. losec, omeprazole). If you suffer from reflux or GERD try to identify and address the cause. (TIP: The cause in most is not high stomach acid - see "What you really need to know about reflux and heartburn").

  • Stomach acid requires adequate zinc, vitamin B6 and B1 levels. So your diet plays an important role. Supplementation may be required.

  • Avoid refined sugar, processed foods, alcohol and excess carbohydrate consumption e.g. pastas, breads, cakes, biscuits, fast foods.

  • Taking herbal bitters or raw unfiltered apple cider vinegar before meals can help increase stomach acid production. Click here for a great drink to sip before meals or at least every morning before breakfast. (This is not recommended if you have a stomach ulcer).

Improve gut motility (the movements of the digestive system)

  • Ginger and the herbal formula Iberogast can aid gut motility. For that reason ginger is added to the drink mentioned above.

  • Have your ileocecal valve assessed. This valve sits between the large and small intestine. An open valve can lead to diarrhea, closed can cause constipation. Dysfunction of this valve can be corrected with some gentle soft tissue work in your lower abdomen and a spinal adjustment / correction. Some chiropractors, applied kinesiologists and functional medicine practitioners know how to do this.

Be wary of antibiotic use

Especially broad spectrum antibiotics that kill not only the bad pathogens but the beneficial ones responsible for making some vitamins, neurotransmitters and that offer immune system support. Antibiotics can be life saving when really needed but over-use can also lead to resistance. They are best saved for life-threatening situations.

Final comment...

With our current Western lifestyle of high stress, processed foods, drug and medication use, SIBO is on the rise. Although it has been known about for the last 50 to 60 years, only recently has SIBO become widely accepted. The benefits of addressing a small intestinal bacterial overgrowth are huge and should always be considered in those suffering gut symptoms, malabsorption, allergies and autoimmune conditions. But be sure to seek help from a holistic health professional.

Interested in learning more about IBS, gut health & gut healing? Join me in The IBS & Gut Healing Facebook Support Group here.

Or perhaps you're already interested in working with me to sort your IBS? Then, check out my free on-demand webinar, my 3 Step IBS & Gut Healing Program or book a free discovery call to see how I can help you.

Other important reads & articles that may be of interest:

You are 90% bugs, but are you the right kind?

Six simple steps to heal your gut and boost your immune system.

All you need to know about probiotics.

What you really need to know about reflux and heartburn.

#SIBO #bacterialovergrowth #irritablebowel #guthealth #ibs #gas #bloating #guthealing

Information provided from Steven Sandberg-Lewis & Allison Siebecker for the Functional Medicine University.

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