Suppose you have been diagnosed with IBS (Irritable Bowel Syndrome). In that case, you must be familiar with the awful symptoms of IBS, such as abdominal pain, bloating, diarrhea or constipation, nausea, anxiety, and so on. But did you know that these symptoms are similar to SIBO (Small Intestinal Bacterial Overgrowth) symptoms?
A study showed that up to 78% of IBS cases are actually SIBO. (1)
What is SIBO?
SIBO stands for Small Intestinal Bacterial Overgrowth and is defined as the presence of excessive bacteria in the small intestine. Bacteria start fermenting carbohydrates, starches, and fibers and produce byproducts, such as gases, which can cause damage to the small intestines' walls and lead to various symptoms. (2)
These symptoms could be bloating and gas, diarrhea and/or constipation, abdominal pain, nausea, belching, reflux, rashes, food intolerances, and many more. The whole process would be expected if it occurred in the large intestine, where it is supposed to happen. (3)
SIBO is categorized into different subtypes:
• Hydrogen-dominant
• Methane-dominant (Intestinal methanogen overgrowth / IMO)
• Hydrogen sulfide-dominant
The main difference between these three types of SIBO is the gases produced by the bacteria (or other organisms) residing in the small bowel. It is also possible that someone has a mixed type of SIBO, meaning multiple types of gases are present simultaneously.
SIBO Myths and Truths
If you have been tested or even treated for SIBO, you might be aware that there are various theories on how to solve this condition. Many of my clients come to me frustrated after trying different medications or approaches that didn't work and feeling lost that they have to learn to live with SIBO forever. I can relate to these feelings as I was also in the same position once.
Even doctors sometimes get confused about why their treatment plan doesn't work. In the case of SIBO, sometimes you need to be a health detective.
Below are 5 misconceptions I gathered that I often hear from clients or read on social media platforms and wanted to shed light on them.
SIBO Myth #1: SIBO can be diagnosed with a stool test
A stool test can be beneficial if we want to see any fungi (Candida) growth or bacterial imbalances present in the large intestine, but it is not the right tool to test for SIBO. Although some markers may indicate SIBO in the stool test (like Klebsiella or Methanobrevibacter smithii), the most commonly accepted diagnostic methods are:
- The 3-hour hydrogen and methane breath test is the most widely used, simplest non-invasive test with lactulose and/or glucose substrate
- Duodenal aspirate cultures (invasive test) (4)
- Alternatively, the IBS Smart (blood) test (as long as it comes back positive for anti-CdtB and anti-vinculin antibodies) to confirm IBS diagnosis and previous food poisoning event as a cause of your symptoms. (5)
All of these tests should be evaluated together with your symptoms and health history.
SIBO Myth #2: SIBO is the cause of all the symptoms
Of course, many clients are happy when they finally get diagnosed with SIBO after years of suffering from IBS symptoms. Unfortunately, SIBO is primarily a consequence of an underlying condition or dysfunction that makes your small intestine hospitable to excess bacteria. Just simply treating SIBO without addressing the contributing factors will cause relapse.
The body has its defense mechanisms to protect itself against bacterial overgrowth. Some of these defense barriers are:
- Adequate stomach acid (6), bile (7), and pancreatic enzyme production (8)
- Well-functioning immune system (9)
- Intact ileocecal valve (10)
- Proper gut motility (or Migrating Motor Complex – a clearing motion of the gut to transfer remaining food particles and bacteria towards the colon) (11)
- Healthy gut microbiome
Anything that negatively influences these barrier functions increases the risk for SIBO. Other contributing factors such as medications (especially PPIs), environmental toxins, or abdominal surgeries (C-section, endometriosis, gallbladder removal) may predispose someone to develop SIBO. (12)
SIBO Myth #3: Antibiotics are enough to get rid of SIBO
Many doctors prescribe Xifaxan (Rifaximin) as the most popular antibiotic for SIBO for hydrogen overgrowth, as well as additional antibiotics such as Neomycin/ Metronidazole in the case of a methanogen overgrowth. (1) These indeed reduce bacterial overgrowth, but most clients relapse as soon as they come off the medications. Why is that happening so often?
I believe the main reason is that antibiotics don't address the underlying causes. Other reasons can be that some people may need several rounds of antibiotics to see results; some may not even react to the meds. The same goes for herbal antimicrobials. Biofilm formation also needs to be considered, which means that bacteria hide behind a protective layer that makes them resistant to any medications. (13)
SIBO Myth #4: Diet alone can cure SIBO
So far, I haven't found any evidence that would show that diet alone can cure SIBO. The only exception is the 14-day-long Elemental Diet, which has an 80% success rate in SIBO treatment. An elemental diet is a liquid formula composed of amino acids, fats, sugars, vitamins, and minerals that can be used for symptom management and treatment. (14)
There is a lot of information and discussions about the different diets that can be used for SIBO. The following diets are mainly recommended for SIBO: Low-FODMAP, Gut And Psychology Syndrome diet (GAPS), Specific Carbohydrate Diet (SCD), SIBO Specific Food Guide (SSFG), Bi-phasic diet, Fast Tract Diet, Paleo and Ketogenic diet, and so on. So overwhelming, right?
The FODMAP diet (Fermentable, Oligo-, Di-, Mono-saccharides, and Polyols) has gained popularity among IBS and even SIBO patients as a dietary approach to managing functional digestive disorders. (15) It is excellent for symptom management, reducing the uncomfortable symptoms of bloating, gas, and diarrhea by removing certain carbohydrates, but these foods are rarely the root cause of the issue.
Maybe you start strictly cutting out all of the high-FODMAP foods, but several months later, you still get stuck on the low-FODMAP diet, and you keep restricting more and more foods that lead nowhere good. FODMAPs are actually beneficial for good bacteria in the colon, so long-term use of this diet might not be the best idea.
Generally, all of these diets can help reduce symptoms and inflammation and identify triggering foods by removing certain carbohydrates, but they won't solve the root causes of the overgrowth. Deliberately starving bacteria may cause them to be inactivated and dormant.
Many people get stuck on the elimination phase of diets for too long due to food fear or think they might relapse. A reintroduction phase should follow every elimination phase to expand the diet as much as possible.
A general anti-inflammatory food plan can be beneficial, but remember, what works for one will not work for all.
SIBO Myth #5: Probiotics are a cure for SIBO
Probiotics for SIBO are pretty controversial.
Some practitioners say they are necessary, and some say no because they feed the bacteria! So, where is the truth?
The truth is – what many of you hate hearing – it depends! As this can be individual. Some clients feel better when adding probiotics later, which I call 'in the gut-healing phase.'
High-potency multi-strain probiotics tend to worsen the symptoms, while certain specific bacteria strains can be beneficial. It is especially true when somebody has histamine intolerance, for instance, where strains matter a lot!
There are more and more studies coming out on the effects of specific probiotic strains on SIBO. One example is Lactobacillus reuteri (DSM 17938). According to a study, Lactobacillus reuteri was found to lower methane production and reduce chronic constipation, but no effect was seen on lowering hydrogen levels. (16)
A meta-analysis published that "the present findings indicated that probiotics supplementation could effectively decontaminate SIBO, decrease H2 (hydrogen) concentration, and relieve abdominal pain, but were ineffective in preventing SIBO." (17)
Generally, Saccharomyces boulardii (a beneficial yeast) (18) and soil-based organisms (19) are well tolerated as they are less likely to colonize the small intestine.
The Bottom Line
Finding out what type of SIBO you have can be a good start, as different SIBO types require different approaches.
SIBO is a complex functional disorder in many cases. It requires a holistic approach, such as customized food plans, lifestyle changes, healthy sleep hygiene, conventional or herbal treatments, prokinetics, vagus nerve stimulation, etc. But the most important thing is to find the 'why", the root cause(s) behind your condition.
In addition, I want to highlight that there is no one-size-fits-all approach to defeating SIBO. Some clients improve on herbal antimicrobials; some may get better after taking probiotics and prebiotics, while others may improve after they work on their digestive function, gut motility, or nervous system.
Just because one approach hasn't worked for you, don't give up! Keep going and try another one. Trust your body that it can heal.
This post is only for informational purposes and is not meant to diagnose or treat any disease. I advise consulting with your healthcare practitioner regarding any treatment options or dietary changes.
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Alexandra is a Functional Medicine Certified Health Coach & Holistic Nutritionist specializing in IBS, SIBO, and Gut Health. She helps her clients identify the root causes of their chronic gut issues with functional testing, supporting their bodies holistically and implementing the necessary lifestyle changes long-term to regain control of their bodies and enjoy food freedom. Book your FREE SIBO Assessment call now >>>