By The Healthy Gut

What You Need To Know About SIBO

In Part 2 of our blog on what you need to know about SIBO, we’ll cover what SIBO actually does to you, the difference between hydrogen and methane dominant SIBO, your treatment options and what supportive practices you could consider.

In Part 1 we covered symptoms, risk factors and associated conditions, what SIBO is and why you should treat it, finding a practitioner and testing. If you missed it, head over to What you need to know about SIBO – Part 1.

What Does SIBO Do To You?

Knowing what SIBO actually does to your body can help to explain some of the health concerns that you might be dealing with. It will also help you to feel more empowered to begin tackling your SIBO.

Under normal circumstances the digested food passes through your small intestine, flowing over your villi and microvilli, which absorb the nutrients in your food. However, when you have SIBO the bacteria digest it instead, which causes fermentation. A by-product of the bacteria’s fermentation is methane and/or hydrogen gas, which is only produced by the bacteria and not our bodies. These gases cause bloating, wind, cramping, diarrhoea, burping, constipation and more. It is also believed this gas can make the lining of the gut permeable, also known as leaky gut syndrome. This allows food particles through to the bloodstream, which creates an immune response (meaning, your immune system goes on the defensive thinking the food particles are an invading force).

The other side effect of SIBO is damage to the villi and microvilli, which results in nutrients not being absorbed. When the bacteria digest your food, it means they’re taking a lot of the nutrients before they make it to you, which leads to malabsorption of monosaccharides, amino acids, vitamins (especially B12 and folic acid) and minerals (especially magnesium, iron and calcium). Some side effects of poor nutrient absorption can include:

✓ Fatigue

✓ Hormonal imbalances

✓ Restless leg syndrome

Other damage caused by the bacterial overgrowth can be the impairment of the natural muscular wave, the Migrating Motor Complex (MMC), that helps to push food along the digestive tract. Learn more about this here on our Migrating Motor Complex podcast with Dr Allison Siebecker. The migrating motor complex occurs in between meals and overnight when we have been fasting.  When it is impaired, it further increases the time food spends in the small intestine, thus increasing its ability to be fermented by bacteria. This is why it is often recommended that SIBO patients leave 4-5 hours between meals and fast for at least 12 hours overnight, to help support the MMC.

Foods containing fermentable fibre, starch, lactose and fructose can make SIBO symptoms worse. Foods that contain gluten, grains, starches like potatoes, legumes and pulses, fruits and some vegetables are generally problematic. And despite the promotion that we should be having a high fibre diet and use fibre supplements, this only exacerbates the problem and people suffering SIBO will feel worse, not better.

SIBO generates toxins, which put pressure on the lymphatic system, the immune system and our body’s own detoxification system. Unfortunately, SIBO goes largely undiagnosed which can result in years of damage to the small intestine. People may develop intolerances to certain foods like gluten, lactose or fructose, as the small intestine becomes less equipped to manage it. SIBO patients are also more likely to become sensitive to histamines, salicylates and oxalates in foods.

SIBO is a major cause of Irritable Bowel Syndrome (IBS), and is estimated to be the underlying cause of IBS in 60% of cases. It is difficult to treat other digestive problems if SIBO remains present, and the longer it remains in the small intestine, the more damage it can cause. Read our 7 Signs Your IBS Could Be SIBO article for more information.

Rebecca Coomes The Healthy Gut Blog Post What You Need To Know About Sibo Ii Blog

What’s The Difference Between Hydrogen And Methane Dominant SIBO?

You may have heard that there are two different types of SIBO: hydrogen and methane SIBO. If you’re hydrogen levels are the highest, then you have hydrogen-dominant SIBO. If you’re methane levels are the highest, then you have methane-dominant SIBO. A diagnosis of hydrogen or methane SIBO doesn’t mean you only have that type of gas present.  You can have both types of gases, it’s just that one is more dominant than the other. There is a third type of overgrowth in the small intestine; SIFO or Small Intestinal Fungal Overgrowth.  Unfortunately, there is no test currently available to accurately diagnose this overgrowth, however we understand that one is being developed and we hope this will be avilable for patients in the near future.

So, The Main Points To Remember Are:

  • Bacteria produces hydrogen which can quicken the transit time of food through the intestines
  • Archaea produces methane which can slow the transit time of food through the intestines
  • Hydrogen SIBO usually causes diarrhoea, and is sometime referred to as SIBO-D
  • Methane SIBO usually causes constipation, and is sometimes referred to as SIBO-C
  • Breath tests for SIBO will measure levels of methane and hydrogen. Read more about SIBO breath tests
  • There is not currently a test available for SIFO

Rebecca Coomes The Healthy Gut Blog Post What You Need To Know About Sibo Ii Blog

What Are The Treatment Options For SIBO? 

Currently, SIBO can be treated through three options: antibiotics, herbal antibiotics and the Elemental Diet. Listen to Dr Nirala Jacobi discuss the SIBO Bi-Phasic diet, testing and herbal treatments

Some patients only need to do one of the three treatment options to recover from SIBO. However, for two-thirds of people, SIBO is a chronic, recurring condition and multiple rounds are required of one or all three of the available treatments.


Antibiotics are often a preferred treatment option by gastroenterologists and patients alike, as they seek to attack the bacterial overgrowth quickly. Rifaximin and Neomycin are the most commonly prescribed antibiotics for SIBO, as they are almost completely non-absorbable and stay within the small intestine. This means they have a localised action and don’t cause systemic or widespread side effects.

Herbal Antibiotics

Herbal antibiotics also seek to attack the excess bacteria directly by reducing the number of bacteria living in the small intestine. Herbs are often the first choice for alternative practitioners, naturopaths and integrative physicians. They do take longer to take effect, so for every week on an antibiotic, two weeks are required on a herbal antibiotic. Studies have shown that herbal therapies are as effective as Rifaximin and have a similar response rate and safety profile. Some of the most commonly used herbs include allicin, oregano, berberine and neem, among others. Like all treatments, the correct herbal protocol needs to be determined for each individual patient and their specific type of SIBO with a qualified Practitioner.

Elemental Diet

The Elemental Diet replaces meals with a pre-digested liquid diet, which seeks to starve the bacteria while providing the individual with amino acids, carbohydrates, fats, vitamins and minerals, which are absorbed in the upper digestive tract. The Elemental Diet can be made at home or purchased in over-the-counter formulations. Some formulations taste better than others, and this diet can be challenging, as it requires a complete liquid diet for at least two weeks. Some patients also complain of dramatic weight loss, which can be problematic for those already underweight. The Elemental Diet is has a high success rate in the treatment of SIBO, but it has many challenges, including cost, taste, food deprivation and weight loss. It is often a last resort for patients.

Rebecca Coomes The Healthy Gut Blog Post What You Need To Know About Sibo Ii Blog


In addition to the treatment protocol, a patient’s nutrition is important in supporting the recovery from SIBO. It is currently believed that diet alone cannot cure SIBO, and instead is used to support treatment and provide relief from digestive symptoms. A restricted diet is designed to be used only for a short time. It is important to reintroduce a wide range of foods and fermentable fibres, as they feed the broader gut microbiome. In addition, it needs to be understood why the body developed SIBO in the first place.

Just as bloating can be a symptom of SIBO, SIBO is a symptom of an underlying condition that has allowed the bacteria to migrate and multiply in the small intestine.  The normal functioning of your small intestine has failed, so it is important to understand what has gone wrong and address that in order to support the likelihood of a permanent recovery from SIBO.

Check Out Our Handy SIBO Risk Factors Download Here


There are several diets that can be followed by SIBO patients. Whilst diet cannot cure SIBO, it can be extremely beneficial in reducing painful and uncomfortable symptoms.  Some diets have been developed specifically for SIBO patients, whereas others have been developed for other conditions, but can be used successfully by some SIBO patients.  Finding the diet that suits you can take time and experimentation.  Dr Allison Siebecker recommends choosing one diet and sticking with it for several weeks to determine if it is suitable for you.  Immense confusion can ensure when SIBO patients try to compare all SIBO diets against each other, as what is suitable for one diet may not be suitable on another.  Hear SIBO nutritionist Kristy Regan speak about finding a nutritional program that’s right for you.

SIBO Specific Food Guide

Dr Allison Siebecker developed the SIBO Specific Food Guide specifically for SIBO patients after years of clinical experience.  She combined the Specific Carbohydrate Diet and the Low FODMAP Diet. This protocol restricts a broad range of fermentable carbohydrates and is more limiting that some of the other diets.  This diet is great for people who are highly sensitive to a broad range of foods or those with a more extreme case of SIBO. Read more about the SIBO Specific Food Guide.

SIBO Bi-Phasic Diet

Australia’s leading SIBO specialist, Dr Nirala Jacobi, further developed the SIBO Specific Food Guide, breaking it into two phases, hence the name ‘Bi-Phasic’. Phase 1 is the most restrictive, and is used to help calm digestive symptoms, and is often used prior to treatment commencing.  Phase 2 introduces more fermentable carbohydrates and allows for greater quantities of certain foods.  This is the protocol Rebecca Coomes followed and what her SIBO Cookbooks are based on.  This protocol works well for people who prefer structure and rules to their treatment plan. It can be meat heavy, so may be difficult for vegetarians and vegans. However, Dr Jacobi is developing a version for vegetarians and vegans so we look forward to sharing this with you in the coming months. Read more about the SIBO Bi-Phasic Diet.

Rebecca Coomes The Healthy Gut Blog Post What You Need To Know About Sibo Ii Blog


The Low FODMAP Diet was by researchers at Monash University for IBS/FGID patients to help control gastrointestinal symptoms associated with those conditions. The diet targets a specific group of short-chain carbohydrates that are poorly absorbed: Fermentable Oligo-, Di-, Mono-saccharides And Polyols.  This diet is less strict than the previous diets and can be used successfully by patients with mild SIBO or symptoms, prevention once tolerances have expanded, underweight patients, vegetarians or vegans.  Read more about the Low FODMAP Diet here.

Cedars-Sinai Diet

The Cedars-Sinai Diet (C-SD) is probably the easiest diet to follow and was developed by Dr Mark Pimentel, one of the leading researchers on IBS and SIBO. It does allow a moderate intake of grains and starches, which is why some people prefer to follow this diet. This diet can be suitable for people with mild SIBO or symptoms, prevention once tolerances have expanded, underweight patients, vegetarians or vegans.  Read more about the Cedars-Sinai Diet here.

Fast Tract Diet

The Fast Tract Diet was developed by Dr Norm Robillard after he suffered from terrible acid reflux for many years.  This diet determines the fermentation potential (FP) of foods, with patients eating to a certain daily FP allowance. This diet works well for people who like an amount of freedom during their day but who are comfortable tallying daily points. Listen to Dr Robillard join Rebecca Coomes on The Healthy Gut podcast to explain the diet.

Specific Carbohydrate Diet

Originally developed for children with coeliac disease, the Specific Carbohydrate Diet was brought to the limelight in Elaine Gottschall’s book Breaking the Vicious Cycle. While not specifically a SIBO diet, some patients may find symptomatic relief when following it. It can be used by patients with moderate SIBO, Inflammatory Bowel Diseased, Coeliac Disease or diarrhoeal disease.

Gut And Psychology Syndrome (GAPS)

The Gut and Psychology Syndrome (GAPS) Diet was developed by Dr Natasha Campbell-McBride, after her son suffered from autism and was greatly helped by the Specific Carbohydrate Diet. The GAPS Diet has been further modified from the SCD Diet, and can be particularly helpful for autistic patients.

What Supportive Practices Can Be Useful When Treating Your SIBO?

SIBO generally doesn’t develop in isolation.  Many things have become dysfunctional in the body to allow bacteria to overgrow.  Using this time to reflect on your nutrition, how you move your body, lifestyle factors such as sleep and stress and your mindset can be really powerful when returning to health.

The 5 Key Pillars to Health address the most important elements of supportive practices for supporting your SIBO journey.

Rebecca Coomes The Healthy Gut Blog Post What You Need To Know About Sibo Ii Blog

5 Key Pillars To Health


The first step to regaining your health is to become aware of how you are feeling. Understanding how to listen to your symptoms and what they may mean is an important first step in your recovery.

✓ Listen to the symptoms your body is sending you

✓ Calming down will have a positive impact on your gut

✓ Track your food and symptoms to see patterns

✓ Acknowledge your journey to healthy has now begun

✓ Use handy tools and resources to support your Awareness


Nutrition is vital to living a healthy gut life. With SIBO, the food you eat can help or hinder your progress. Awareness of what you eat and how you eat is essential to your recovery.

✓ Enjoy food. It is our greatest source of nourishment

✓ Eat the foods that help, not hinder, your recovery

✓ Watch the timing and quantity of your food to manage your symptoms

✓ Make a plan and stick to it

✓ Enjoy delicious recipes and menu planning tools to support your Nutrition 

Rebecca Coomes The Healthy Gut Blog Post What You Need To Know About Sibo Ii Blog


We were designed to move, yet many of us find ourselves spending several hours a day being sedentary. Our gut can respond positively to exercise and movement. Understand how you move your body and what type of movement will help or hinder your recovery.

✓ Move your body to move your gut

✓ Find the right type of movement for your current health state

✓ Exercise to release endorphins and feel better

✓ Get outside, breathe fresh air and connect with nature

✓ Get the support you need to bring Movement into your day


What we think has an enormous impact on our health. When you have been unwell for some time, it can be very easy to fall into a negative mindset. Turning negative thoughts into positive beliefs will support you to achieve your wellness goals.

✓ Write down 5 things that make you happy everyday

✓ Focus on what you can do, not what you can’t do

✓ Meditate, breathe or practice yoga to calm the mind

✓ Make time for yourself. You will feel better for it

 Use handy tools and resources to support your Mindset


The way you live your life is fundamental to your recovery. Stress, sleep, relationships, social activities, relaxation and goal setting play an important role in how quickly you regain your health.

✓ Get plenty of sleep to support your recovery

✓ Address your stress levels.  Stress has a negative impact on the gut

✓ Spend time with people who support your health journey

✓ Prioritise your health. You’re worth it

✓ Implement easy tips to improve your Lifestyle

This is Part 2 of a 2 part series on understanding SIBO.  Check out What you need to know about SIBO – Part 1 if you missed Part 1.

Rebecca Coomes The Healthy Gut Blog Post Beauty Is More Than Skin Deep Blog