Are you struggling with unexplained digestive issues, chronic bloating, or fluctuating bowel habits? You could be suffering from Small Intestinal Bacterial Overgrowth (SIBO). is when too many bacteria set up camp in your small intestine—a place where bacteria aren’t meant to be in large numbers! When this happens, it can lead to all kinds of frustrating symptoms, from gas to nutrient deficiencies, affecting your gut health. But did you know that SIBO can also affect your mental health, causing symptoms like anxiety, depression, and brain fog?
I was diagnosed by one doctor after a frustating 12 years of unexplained symptoms and tens of doctors telling me I was just ‘too stressed’. Their common diagnosis was IBS and they told me to ‘just watch more TV and stress less’. The doctor who actually listened, immediately explained the 3 different options of SIBO. Let’s get into them:
1. Hydrogen-Dominant – SIBO Type 1
Hydrogen-Dominant SIBO, or simply Hydrogen SIBO, is one of the most frequently diagnosed types of SIBO. It occurs when bacteria in the small intestine produce excessive hydrogen gas as they ferment undigested food. This overproduction of hydrogen can lead to classic digestive symptoms, as well as mental symptoms like brain fog and mood changes, which are common but often overlooked. Let’s explore the signs and treatments specifically suited for Hydrogen SIBO, including important dietary considerations.
What is Hydrogen SIBO?
In a normal, healthy gut, bacteria are largely concentrated in the large intestine, where they play a role in breaking down fiber and supporting digestion. However, in Hydrogen SIBO, bacteria live in the small intestine, where they break down carbohydrates too early! This process leads to a surplus of hydrogen gas, which can cause symptoms like bloating, diarrhea, and abdominal pain.
Did You Know? Hydrogen SIBO is the most common type of SIBO diagnosed in individuals with IBS (Irritable Bowel Syndrome), especially those experiencing IBS-D (diarrhea-predominant IBS). A 2020 study found that 35% of IBS patients have SIBO at some point in their life.
Common Symptoms of Hydrogen SIBO
Hydrogen SIBO is associated with several digestive and mental symptoms. Here are the most common indicators:
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Digestive Symptoms:
- Bloating and Abdominal Pain: Many people experience bloating that worsens after meals and persistent abdominal discomfort.
- Frequent Diarrhea: Loose stools or diarrhea are common, as hydrogen gas irritates the intestines.
- Excessive Gas and Belching: The surplus hydrogen gas can lead to uncomfortable gas and frequent belching.
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Mental and Cognitive Symptoms:
- Brain Fog: Difficulty with focus, mental fatigue, and a “cloudy” feeling are often reported and may be linked to inflammation and nutrient malabsorption.
- Mood Changes: Anxiety, irritability, and low mood can be triggered by gut inflammation, affecting the gut-brain axis.
If you think these symptoms describe you, it might be a good idea to get tested.
Quick Fact: The gut-brain axis is a communication system linking the gut and brain. When gut health is disrupted, it can impact mental clarity, mood, and even stress levels.
Treatment Options for Hydrogen SIBO
Treating Hydrogen SIBO involves reducing bacterial overgrowth and relieving symptoms, often through a combination of antibiotics, herbal antimicrobials, and dietary management.
- Antibiotics: Rifaximin is the most commonly prescribed antibiotic for Hydrogen SIBO. The main reason it is prescribed instead of other antibiotics is because it works mainly in the small intestine without disrupting the rest of the gut microbiome.
- Herbal Antimicrobials: Natural alternatives such as oregano oil, berberine, and neem can effectively reduce bacteria and may be used alone or with antibiotics.
- Prokinetics: Prokinetic supplements are often recommended to improve gut motility, or digestion speed, sometimes to prevent the bacteria from coming back.
2. Methane-Dominant SIBO (Intestinal Methanogen Overgrowth, IMO)
Methane-Dominant SIBO, also known as Intestinal Methanogen Overgrowth (IMO), is a specific type of SIBO where methane-producing organisms, called archaea, contribute to symptoms like constipation, bloating, and sluggish digestion. If constipation and a “heavy” feeling in the abdomen are your main symptoms, Methane SIBO might be the cause. Let’s dive into the unique signs, testing methods, and targeted treatments for Methane SIBO, including effective dietary strategies.
What Makes Methane SIBO Different?
Methane SIBO is unique because it involves archaea, which are not actually bacteria, but old and small organisms. This is also why the actual name for Methane SIBO is IMO. These archaea produce methane gas when they ferment food in the small intestine, slowing down gut movement (motility) and leading to constipation rather than diarrhea.
Did You Know? Methane gas doesn’t just affect digestion; it directly impacts gut motility. Research shows that high levels of methane slow down the movement of food and waste through the digestive system, which is why constipation is a primary symptom of Methane SIBO.
Common Symptoms of Methane SIBO
Methane SIBO has a set of typical symptoms that can change digestion and impact daily life. Here are the most common indicators:
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Digestive Symptoms:
- Constipation: The slowed gut motility caused by methane results in constipation and infrequent bowel movements.
- Chronic Bloating: constant bloating and a “heavy” feeling in the abdomen are common complaints.
- Fullness and Sluggish Digestion: Many people with Methane SIBO feel overly full after meals due to slowed digestion.
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Mental and Cognitive Symptoms:
- Brain Fog: Methane SIBO may affect mental clarity, leading to difficulty with focus or concentration. Some people feel like they’re drunk, even though they’re sober.
- Mood Changes: Low energy, irritability, and low mood are often reported, likely due to nutrient malabsorption and the gut-brain connection.
Quick Fact: Methane SIBO has been linked with IBS-C (constipation-predominant IBS). In fact, many individuals diagnosed with IBS-C may actually have Methane SIBO.
Treatment Options for Methane SIBO
Treating Methane SIBO can be challenging because archaea don’t respond to typical antibiotics used for bacterial SIBO. Here are the main treatment approaches:
- Combination Antibiotics: Methane SIBO often requires a combination of rifaximin and neomycin. This combo targets both bacteria and archaea, helping reduce symptoms by addressing the methane-producing organisms.
- Herbal Treatments: Herbal antimicrobials, like allicin (from garlic), oregano oil, and berberine, have shown promise in reducing methane production. Some people find these natural alternatives effective, especially if antibiotics aren’t suitable.
- Prokinetics: These medications or supplements help stimulate gut motility, keeping food and bacteria moving smoothly through the digestive tract. Prokinetics are particularly important for Methane SIBO, as they can prevent recurrence by supporting regular gut movement.
- Lifestyle Adjustments: Managing stress, getting regular exercise, and improving sleep quality can positively impact gut motility and overall SIBO management.
Quick Fact: Research indicates that combining rifaximin and neomycin is often more effective for reducing methane levels than using a single antibiotic for Methane SIBO, especially for those dealing with severe constipation. Archaea don’t respond to standard SIBO treatments.
Did You Know? Methane SIBO is one of the toughest types to treat because archaea are very persistent. Getting rid of it usually requires a mix of treatments, including changes in diet, antibiotics, prokinetics, and lifestyle adjustments.
By combining targeted treatments, dietary modifications, and lifestyle changes, many people find relief from Methane SIBO symptoms, experiencing improved digestive comfort and overall well-being. Partnering with a healthcare provider is essential to develop a comprehensive plan suited to your unique needs and symptoms.
3. Hydrogen Sulfide SIBO – the newest SIBO type
Hydrogen Sulfide SIBO is the rarest and the new kid on the block. Unlike Hydrogen and Methane SIBO, this type produces hydrogen sulfide gas, which can lead to unique symptoms like sulfur-smelling gas, fatigue, and skin issues. If your symptoms don’t match the usual SIBO profile, Hydrogen Sulfide SIBO might be the cause. Here’s an overview of what makes this type of SIBO different, how to test for it, and which treatments and dietary changes can help.
What is Hydrogen Sulfide SIBO?
In Hydrogen Sulfide SIBO, certain bacteria in the small intestine produce hydrogen sulfide gas, which can lead to a distinctive “rotten egg” odor in gas and stools. This type of gas can affect more than just digestion; hydrogen sulfide is known to impact energy levels, inflammation, and even skin health, making Hydrogen Sulfide SIBO particularly challenging.
Did You Know? Hydrogen sulfide gas affects not only the digestive tract but also other systems in the body. In high amounts, it’s been associated with fatigue and increased oxidative stress, which can cause skin issues and low energy.
Recognizing the Symptoms of Hydrogen Sulfide SIBO
Hydrogen Sulfide SIBO comes with a set of unique symptoms that can make it harder to identify. Here are the most common signs:
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Digestive Symptoms:
- Sulfur-Smelling Gas: Gas with a “rotten egg” smell is a hallmark of Hydrogen Sulfide SIBO.
- Abdominal Pain and Sensitivity: Many people experience abdominal discomfort or pain that worsens after meals.
- Variable Bowel Habits: Some experience diarrhea, while others may have a mix of diarrhea and constipation.
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Mental and Physical Symptoms:
- Fatigue and Low Energy:Hydrogen sulfide can get in the way of the body’s energy-making process, which may lead to constant tiredness and low energy.
- Skin Issues: Some people with Hydrogen Sulfide SIBO report skin problems, including acne or rosacea, possibly due to inflammation.
- Brain Fog: Mental clarity can be impacted, making it harder to focus or causing a “foggy” feeling.
Quick Fact: Large amounts of hydrogen sulfide gas can get in the way of how our cells make energy. This might be why people with this type of SIBO often feel tired and low on energy.
Treatment Options for Hydrogen Sulfide SIBO
Hydrogen Sulfide SIBO needs a unique treatment approach since it involves bacteria that might not respond to standard SIBO treatments. Here are some options:
- Antibiotics: Like for all types of SIBO, antibiotics like rifaximin are often used. To target hydrogen sulfide SIBO specifically, it’s commonly combined with in with metronidazole.
- Dietary Adjustments: Limiting foods high in sulfur (such as red meat, eggs, dairy, and cruciferous vegetables like broccoli and cauliflower) can help reduce gas production and alleviate symptoms.
- Herbal Antimicrobials: Herbs such as oregano oil, allicin (from garlic), and berberine can effectively reduce bacteria contributing to hydrogen sulfide production.
- Probiotics and Supplements: Specific probiotics that support gut health without producing additional gas, such as certain strains of bifidobacteria, can be beneficial. Molybdenum supplements are sometimes recommended to help the body process sulfur effectively, reducing symptoms.
Quick Fact: Unlike other SIBO types, Hydrogen Sulfide SIBO often requires dietary sulfur reduction to directly limit gas production. This means avoiding certain foods temporarily to ease symptoms.
Dietary Tips for Managing Hydrogen Sulfide SIBO
Diet plays a critical role in managing symptoms of Hydrogen Sulfide SIBO. Here’s how dietary changes can help reduce sulfur production and improve comfort:
- Limit Sulfur-Rich Foods: Reducing foods high in sulfur, such as red meats, eggs, dairy products, and sulfur-rich vegetables (like broccoli, cauliflower, and Brussels sprouts), can help minimize gas production and ease symptoms.
- Use Low-FODMAP Diet for Symptom Relief: A Low-FODMAP diet can further help by reducing fermentable foods that feed bacteria, which helps to get immediate symptom relief: like less bloating and pain. However, Low-FODMAP does not directly target sulfur and should be used to manage symptoms rather than as a cure.
- Individualized Diet Plan: Each person’s tolerance to foods can vary, so working with a healthcare provider or dietitian to create a personalized diet plan can help manage symptoms effectively while ensuring nutritional needs are met.
Did You Know? Sulfur is an essential nutrient, so restricting it permanently isn’t advisable. The goal with dietary adjustments is to reduce sulfur temporarily, managing symptoms until gut health improves.
Is there a fourth SIBO type?
At this moment, there is not. However, it is possible that you have a mix of one or more types of SIBO. This may make your symptoms a little straightforward as well, since you might have both constipation and diarrhea on different days for example.
How do I know which SIBO type I have?
Hydrogen and Methane SIBO
For both Hydrogen and Methane SIBO, a breath test can be done that measure gas levels in your breath. These work as follows:
- Preparation: You’ll follow a specific low-carbohydrate diet for 24 hours and then you fast 12 hours before the test to ensure accurate results.
- Baseline Sample: The test begins with a baseline breath sample to measure existing gas levels.
- Drink a Sugar Solution: After the baseline, you’ll drink a sugar solution (like lactulose or glucose) to encourage gas production by bacteria. Yes, this may mean you feel horrible during the test. But no noticeable reactions doesn’t mean you don’t have SIBO! As difficult as it is, be patient for the results.. I know I couldn’t wait. The little drink tastes so sweet it’s almost bitter, but you only need a small sample, so it’s very doable.
- Breath Sampling Over Time: You’ll provide breath samples every 15–20 minutes for about two to three hours.
- What do breath test results mean?:
– If hydrogen levels rise more than 20 parts per million (ppm) before 90 minutes in the test, you have hydrogen SIBO. (If they go up after 90 minutes, they’re likely going up because of bacteria in your large intestines, which is not an issue).
– For methane, this is 10 ppm before 90 minutes.
Hydrogen Sulfide SIBO
So what about Hydrogen Sulfide SIBO then? It is a little more complex than for the other two types, since it’s so new. There are a few newer breath tests companies that offer tests for all three types. If you suspect you might have H2S SIBO, be sure to ask for one of those if possible.
Some other options might be:
- Symptom-Based Diagnosis: Because of the distinctive sulfur-related symptoms, doctors may consider Hydrogen Sulfide SIBO based on your symptom profile.
- Stool Testing: In some cases, stool tests can help identify bacterial imbalances that are often associated with hydrogen sulfide production, adding further clues.
Conclusion
I know dealing with SIBO is overwhelming. There’s a lot of confusing information out there and both the symptoms and the journey to relief are complex. Understanding and figuring out the three types —Hydrogen, Methane, and Hydrogen Sulfide— is a good starting point to tackle symptoms. The solution to SIBO and being symptom free is usually not clear cut. Most people need a combination of antibiotics, herbal remedies, (temporary) diet tweaks and lifestyle changes. But ultimately, it is possible to get SIBO free!
A good place to start is finding a doctor or healthcare provider that is willing to help you figure out whether you have SIBO and if so, which type. Yes, it might be frustrating because not all doctors are as helpful as you need them to be, but a personalised approach to SIBO is the best way to get relief. Thus, I can only tell you to keep trying to find a good doctor.
