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SIBO - what's the story?

So you keep hearing about SIBO. What's the story? What is SIBO, how do I know if I have it, and how do I get rid of it?

SIBO stands for Small Intestinal Bacterial Overgrowth. Normally we only have bacteria in our large intestine. There is very little, if any, in our small intestine. SIBO is akin to 'being in the wrong place at the wrong time!' Too much bacteria present in our small intestine leads to gas production, malabsorption of nutrients, and ongoing issues associated with that.

We test for SIBO using a breath test that measures the presence of hydrogen and methane generated over a 3-hour period after ingesting a liquid testing substrate (lactulose). There should be minimal gas produced. In about 20% of the population, this isn't the case however as you have microbes in your small intestine that shouldn't be there. If you have bloating, or are gassy - read on!

Image showing small intestine overgrown with bacteria.
Small Intestine should be relatively free from bacteria - not like the image shows.

What normally happens after we eat?

Our small intestine is where our food is broken down (digested), by our gastric juices, allowing the nutrients from those foods to be available for absorption from our small intestine into our bloodstream. The nutrients are absorbed through villi located in our small intestine. Villi are finger-like projections which are richly supplied with blood vessels as shown below. They are present in the inner lining of the small intestine and help in the absorption of nutrients by increasing the surface area available for absorption.

Picture of small and large intestine with arrow showing microscopic view of villi in small intestine
Location of Small Intestine with villi highlighted

What's the story with SIBO?

When bacteria is present in our small intestine, they 'greedily' consume the nutrients from our foods before they get absorbed into our bloodstream, which lies directly under the villi (shown by the red and blue lines in the image above). As the bacteria are greedily consuming the broken down foods, they produce gas in the process. That's why we are 'gassy' when we have SIBO. Are you gassy? Have flatulence and belching? Could you have SIBO?

What is the fuel for SIBO

FODMAP foods are the fuel for SIBO. FODMAP stands for:

  • Fermentable

  • Oligosaccharides - wheat, rye, onions, garlic, legumes are some examples

  • Disaccharides (Lactose) - milk, yogurt, cheese are some examples

  • Monosaccharides (Fructose) - honey, apple, sweeteners are some examples

  • and Polyols - from sorbitol and mannitol from some fruits and vegetables

FODMAP foods should pass straight through the small intestine and into the large intestine. Here they get fermented by the bacteria in the large intestine and produce short chain fatty acids (SCFA's). SCFA's keep the integrity of our gut function nice and tight (no leaky gut), limiting any false immune triggering events which means they are anti-inflammatory. This is a great thing as they lower our risks of diabetes, cardiovascular disease, obesity and other chronic health conditions. We want the FODMAP's to make it to the large intestine, and not get 'waylayed by a party happening in the small intestine'.

When FODMAP foods aren't digested correctly, we get IBS (Irritable Bowel Syndrome). It is estimated that up to 85% of all IBS cases are from SIBO.

Symptoms of SIBO

  • Gas and bloating

  • Abdominal cramping

  • Diarrhoea or constipation

  • Fatigue and weakness

  • Anxiety, Depression from nutrient deficiencies needed to make neurotransmitters

  • Brain fog

  • Restless Leg Syndrome

  • Burning Bladder Syndrome

  • Histamine symptoms including headaches, migraines, bladder irritation, eczema, hives and rashes, acne rosacea, heart palpitations, anxiety, insomnia

  • Oestrogen dominance (PMS, PMDD, worsening of peri-menopause symptoms)

  • Fibromyalgia

  • Joint pain

  • Vitamin and Mineral Deficiencies

Consequences of SIBO

  • SIBO is often from not having enough digestive juices, and not having digestive juices means we can't break down our foods properly. You may see undigested food in your poop.

  • Having SIBO means we may end up with nutrient deficiencies, as the gas produced disturbs the brush border enzymes . This could be one of the many reasons you are Iron Deficient. It could also explain why your Zinc levels are low, along with magnesium and our vitamin range. Do you have any nutritional deficiencies?

  • One nutrient Zinc is needed to stimulate HCl (Hydrochloric Acid) which is very acidic, kills pathogens, and is present early on in our digestive processes. Without HCL, pathogens thrive, and in addition our foods don't get broken down into small pieces. This is compounded even more if we don't chew our foods well.

  • It can disrupt our methylation processes, so vital for our health. Methylation is the process in our body where chemical tags are added to DNA, so it quite literally turns genes in our biochemical pathways on or off. This can equal good health or bad health.

  • We can also end up on antidepressants, as the cofactors required to make good neurotransmitters to keep us happy, motivated, and sleeping well, can get consumed by the bacteria. So we can make minimal neurotransmitters.

  • Our small intestine is not only the site for nutrient absorption, but it is also where the majority of our immune system barrier is (our secretory IgA). With gas being produced in the small intestine, this can cause damage to the villi in the small intestine. It can quite literally blow apart the tight junctions keeping that single layer of cells together. With this we can then get leaky gut, where products that should not be in our bloodstream end up with easy access. This can then set up inflammation.

  • We can then develop reactivities to certain foods. Do you have certain foods you know don't agree with you? It could be SIBO. Fix the SIBO and your intolerances may go away.

Types of SIBO

If you've been breath tested and are positive for SIBO, your results can show the type of SIBO that you have. It it based on the type of gas emitted, and can be:

  1. Hydrogen Dominant - this type of gas results in looser poops than normal

  2. Methane Dominant - this type of gas is more associated with constipation

  3. Mixed (Both Hydrogen and Methane) - may appear as diarrhoea, constipated, or normal.

What caused my SIBO?

A list of SIBO causes including lack of digestive acids, enzymes, bile etc
Common causes of SIBO

1. Impaired Motility - indicators could be:
  • Faulty Ileocaecal valve (that sits between your small and large intestine acting like a gate)

  • Gastroparesis - delayed stomach emptying

  • Low secretory IgA resulting in Immunity issues - it's our principle defence against pathogens that penetrate our intestinal barriers

  • Gastroenteritis history

  • Food poisoning history

  • Traveller's diarrhoea history

  • Accidents history - like car, bike, horse, concussion etc

  • Thyroid issues (Hypothyroid)

  • Diabetes, Metabolic Syndrome, Pre-diabetes

  • Chronic infections

2. Impaired Digestion - indicators could include:
  • Belching or gas within 1 hour after eating

  • Heartburn or acid reflux

  • Bad breath

  • Issues digesting meat

  • Feeling excessively full after eating

  • Stomach pain, cramps

  • Seeing undigested food in poops

  • Poops look greasy or are difficult to flush

  • Having high levels of stress or anxiety

  • Faulty Migrating Motor Complex, that stimulates wave-like persistalsis

3. Impaired Gastric Juices for Digestion (low stomach acid HCl, low digestive enzymes, low pancreatic enzymes, and compromised immune system) - indicators could include:
  • History of Appendix removal

  • History of Gall Bladder removal

  • Adhesions from surgeries including Hernia repair, Endometriosis, Ruptured Ovarian Cysts, Laparoscopy, Hysterectomy, Caesarian deliveries, Pelvic Inflammatory Disease

4. Medication Use - types of medications might include:
  • Chronic antibiotic use

  • Antidepressants

  • Antispasmodics

  • Opiates, narcotics

  • Proton Pump Inhibitors (for Reflux)

  • Cholesterol lowering medications (that remove Bile)

  • Thyroid medications

How do I get rid of SIBO?

Let's start by saying it's best to get treatment for this from a qualified naturopath. You don't want to go through the recommended diet and have it fail. It's quite restrictive so you want to give it your best shot once by seeing a qualified naturopath. If that's not an option, you can start to improve this yourself by following a few simple tricks:

  • Chew your food into very small pieces (chewing each mouthful 20 times helps). Chewing well will ensure the digestion process that breaks down our proteins, fats and carbohydrates, works well. It starts with salivary amylase in our mouth, stomach acids (HCl, Pepsin, Lipase), Bile from Liver, and Pancreatic enzymes (Amylase, Lipase, Trypsin, Chymotrypsin).

  • 30 minutes before each meal, drink warm lemon, or Apple Cider Vinegar to stimulate your digestive juices, which are not only important for peristalsis, but are also anti-microbial. They are our natural means of killing off bacteria in the small intestine.

  • Eliminate sugary foods, alcohol and minimise carbohydrates and fermented foods. The bacteria love these foods!

  • Eat Low FODMAP foods for up to 6 weeks (NO LONGER). The Monash University FODMAP Diet app is a great resource to pick the green traffic light foods you can eat.

  • Don't snack between meals - don't keep feeding them! This is also to ensure we reset our migrating motor complex (MMC) which is the peristaltic (wave-like) motion our small intestine makes to send on any undigested food scraps from our small intestine to our large intestine. You hear a 'growling' action when this is happening. SIBO negatively impacts on the MMC. When was the last time you heard growling?

  • Once you've completed the 6 weeks low FODMAP, reintroduce foods SLOWLY, starting at Orange traffic light foods one at a time.

Note: SIBO is difficult to treat and should be undertaken with a qualified Naturopath to help with herbal remedies to 'kill off' bacteria present and supplement so you don't feel ill during this process!

Link between SIBO and Histamine Issues

SIBO has many flow on issues, one of which includes Histamine Intolerance issues. Histamine is largely broken down in our gut by the DAO enzyme which lives in the small intestine. It prevents Histamine getting into our bloodstream. Should histamine get into our bloodstream we can end up with systemic histamine issues - all over our body!

How does this happen? If gas is produced by SIBO, the cells with the DAO enzyme are damaged. DAO is then not available to break down histamine. Leaky gut from disrupted tight junctions also allow histamine to go straight through to the bloodstream. Systemic histamine issues include headaches, migraines, bladder irritation, eczema, hives and rashes, acne rosacea, runny eyes and nose, heart palpitations, anxiety, and insomnia to name just a few. Read my blog on Histamine Intolerance to understand more:

If you would like to discuss your symptoms, organise SIBO breath testing, or undertake the SIBO Bi-phasic diet complete with herbal solutions, then please don't hesitate to make a booking with me. I am qualified in treating SIBO, and have undertaken the procedure myself so can provide some useful tips and tricks.

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