SIBO Breath Test for Accurate Small Intestinal Bacterial Overgrowth Assessment in Singapore
When you’re constantly battling bloating, abdominal pain, or unpredictable bowels and standard scopes or stool tests keep coming back “fine” the answer is often happening higher up: in your small intestine, where bacteria don’t belong in large numbers. Small Intestinal Bacterial Overgrowth (SIBO) is one of the most under-assessed root causes of persistent digestive symptoms, IBS-like complaints, and even seemingly unrelated issues like brain fog and fatigue.
The SIBO Breath Test is a simple, non-invasive at-home test that measures hydrogen, methane, and hydrogen sulphide (H2S) gases produced by bacterial fermentation in your small intestine. Depending on your symptoms, Dr. Menka Gupta selects the right substrate glucose, lactulose, or both to give you the clearest possible picture of what’s happening, and then turns the data into a personalised functional medicine plan.
Find out if SIBO is what’s really driving your symptoms.
A non-invasive breath test available at-home or in-clinic, measuring hydrogen, methane, and H2S interpreted by Dr. Menka Gupta and translated into a personalised plan that targets the cause, not the symptoms.
Get To Know Dr Menka
Dr. Menka Gupta* has been practicing functional medicine since 2012 and is the first Institute for Functional Medicine Certified Practitioner (IFMCP) in South Asia. She has helped more than 12,000+ patients with complex and chronic health issues related to Digestive disorders, Anxiety, Depression, Chronic fatigue, Thyroid, Autoimmunity, Eczema, Autism. She has more than 25 years of experience in the health and wellness field in London and Singapore.
Dr. Menka Gupta*, MBBS, MSc, FMCP-M
IFM-Certified Functional Medicine Practitioner • 25+ Years Experience
✓ Medically Reviewed •
What is SIBO?
SIBO, or small-intestinal bacterial overgrowth, is a condition characterized by an abundance of bacteria growing in the small intestines, causing digestive problems. The small intestine generally has far fewer bacteria than the colon, but the excess bacteria grow on undigested food, causing fermentation of undigested food and gases such as hydrogen, methane, and hydrogen sulfide to form.
The excess gas can interfere with nutrient absorption, potentially leading to malnutrition. Additionally, SIBO symptoms often resemble a number of other gastrointestinal disorders, making early testing crucial for preventing long-term complications of SIBO, including leaky gut syndrome.
SIBO develops when the body’s natural defences against bacterial overgrowth break down. Common contributing factors include:
What is a SIBO Test?
Through a gas analysis of the breath, the SIBO breath test can detect bacterial overgrowth in a person’s small intestinal tract without the need for an invasive procedure. The test will measure the levels of hydrogen, methane, and H2S in a person’s breath after ingestion of a substrate (glucose or lactulose).
Glucose primarily assesses only the upper part of the small intestine, whereas lactulose can determine growth over the entire length. H2S is an indicator of the presence of sulphide-producing bacteria, which are linked to specific constipation types.
Sample collection can be done in two ways: at-home, where the patient uses a SIBO test kit and ships the samples to a laboratory for analysis; or in-clinic, where our Singapore-based team guides the patient through the full 2–3 hour test on-site and manages all sample handling and shipping. Both formats use the same analysis and deliver the same diagnostic accuracy. Laboratory testing of breath samples has become the standard method for confirming SIBO.
Common Signs
Symptoms of SIBO
The most common symptoms of SIBO include:
Types of SIBO Tests
There are three main breath test variants, each with a distinct diagnostic strength:
Glucose Breath Test
Best for detecting overgrowth in the upper (proximal) small intestine. Glucose is absorbed rapidly, so any gas rise within 90 minutes indicates bacterial activity in the upper section.
Lactulose Breath Test
Covers the full length of the small intestine. Lactulose isn’t absorbed, so it travels further, helping detect more distal overgrowth. Slightly higher false positive rate but broader coverage.
Hydrogen Sulphide (H2S) Test
Identifies sulphide-producing bacteria that traditional hydrogen/methane testing misses. Especially relevant for patients with diarrhoea-dominant symptoms or those who’ve tested negative for SIBO despite clear symptoms.
In many cases, combining substrates yields the most complete diagnostic profile, and Dr. Menka Gupta* recommends the right combination based on your symptom pattern.
Who Should Take a SIBO Test?
If any of the following sound familiar, this test is for you:
- ✓Persistent bloating, especially after meals?
- ✓Abdominal pain, cramping, or distension?
- ✓Diarrhoea, constipation, or alternating between both?
- ✓Excessive gas or burping?
- ✓Fatty, foul-smelling stools?
- ✓An IBS root cause that hasn’t responded to typical treatments?
- ✓Skin rashes, eczema, or other inflammatory skin issues?
- ✓Suspected B12 or fat-soluble vitamin deficiencies despite a clean diet?
- ✓Symptoms that worsen with high-FODMAP or high-carb meals?
If you’re nodding your head “YES” to any of these, this is for YOU.
Stop guessing. Stop relying on multivitamins that may or may not be working. Get the data, get a plan, and start feeling like yourself again.
Conditions Addressed
Which Health Issues Does It Help?
The SIBO breath test can help identify SIBO as a root or contributing cause behind a wide range of conditions, including:
- IBS (Irritable Bowel Syndrome), particularly cases that haven’t responded to standard treatments
- Chronic bloating, gas, and abdominal distension
- Constipation, diarrhoea, and alternating bowel patterns
- Leaky gut and gut barrier dysfunction
- Food intolerances and FODMAP sensitivity
- Unexplained nutrient deficiencies, especially Vitamin B12 and fat-soluble vitamins (A, D, E, K)
- Chronic fatigue, brain fog, and low mood
- Rosacea, eczema, and other inflammatory skin conditions
- Autoimmune conditions linked to gut barrier dysfunction
- Histamine intolerance and mast cell activation symptoms
- Post-infectious gut dysfunction (especially after a stomach bug or food poisoning)
- Conditions involving slowed gut motility, hypothyroidism, diabetes, and scleroderma
Why Is SIBO Testing Important?
- Non-invasive and convenient No endoscopy, no biopsy. A series of breath samples collected at home or in-clinic over 2–3 hours.
- Targets the right location Stool tests look at the large intestine. The SIBO breath test specifically targets the small intestine, where the actual overgrowth happens, making it the right tool for the right job.
- Identifies the exact SIBO type Hydrogen-, methane-, or H2S-dominant SIBO, each responds to different assessments. The breath test tells you which type you have, so the protocol matches the cause.
- Catches what other tests miss Standard scopes, stool panels, and blood tests often miss SIBO. If you’ve been told everything is “normal” but still feel terrible, the breath test gives you a different angle that actually finds the issue.
- Maps the location within the small intestine Using glucose or lactulose strategically, the test helps identify whether overgrowth is proximal (upper) or more distal, informing where assessment should focus.
- Targeted, personalised programs Your results feed directly into a customised assessment plan from Dr. Menka antimicrobial protocol, motility support, functional nutrition strategy, and supplement plan built around your specific SIBO type.
- No more guesswork with diet Skip the indefinite Low-FODMAP cycle. Once SIBO is confirmed and removed, you can systematically reintroduce foods rather than restricting forever.
SIBO Breath Test Procedure
The SIBO breath test is a simple, non-invasive test available in two formats: at-home (with a kit delivered to your door) or in-clinic (collected at our Singapore clinic with our team supervising). Both formats use the same preparation protocol, the same lab analysis, and deliver the same accuracy of results. Accurate results depend heavily on following the preparation steps precisely. Diet, fasting duration, and supplement washout all directly affect the readings.
Which Health Issues Does It Help?
The SIBO breath test can help identify SIBO as a root or contributing cause behind a wide range of conditions, including:
- IBS (Irritable Bowel Syndrome), particularly cases that haven't responded to standard treatments
- Chronic bloating, gas, and abdominal distension
- Constipation, diarrhoea, and alternating bowel patterns
- Leaky gut and gut barrier dysfunction
- Food intolerances and FODMAP sensitivity
- Unexplained nutrient deficiencies, especially Vitamin B12 and fat-soluble vitamins (A, D, E, K)
- Chronic fatigue, brain fog, and low mood
- Rosacea, eczema, and other inflammatory skin conditions
- Autoimmune conditions linked to gut barrier dysfunction
- Histamine intolerance and mast cell activation symptoms
- Post-infectious gut dysfunction (especially after a stomach bug or food poisoning)
- Conditions involving slowed gut motility, hypothyroidism, diabetes, and scleroderma
What Will a SIBO Test Tell Me?
The SIBO breath test measures three key gases: hydrogen (H2), methane (CH4), and hydrogen sulphide (H2S) produced by bacterial fermentation in your small intestine. The pattern of gas production and the timing of any rise reveal both whether SIBO is present and what type you have.
Your report covers:
- Presence of SIBO — whether gas levels rise above diagnostic thresholds within the test window
- SIBO type — hydrogen-dominant, methane-dominant (sometimes called IMO Intestinal Methanogen Overgrowth), or H2S-dominant
- Location of overgrowth — based on timing of gas rise, whether overgrowth is in the upper (proximal) or lower (distal) small intestine
- Severity — based on how high gas levels rise and how early in the test
- Symptom correlation — which gas pattern best explains your specific symptom profile
These insights are then translated by Dr. Menka Gupta* into a clear, actionable plan for antimicrobial selection, dietary strategy, motility support, and supplement protocol matched to your specific SIBO type.
What Do I Get with the SIBO Breath Test Program?
- Comprehensive SIBO Breath Test measuring hydrogen, methane, and (where indicated) hydrogen sulphide
- Flexible testing format: at-home kit delivered to your door, or in-clinic appointment at our Singapore clinic, whichever suits you
- Substrate selection guidance: glucose, lactulose, or both, chosen by Dr. Menka Gupta* based on your symptoms
- Full Support and Clear Instructions on Test Preparation and Sample Collection
- 1-hour Dedicated Consultation with Renowned Functional Medicine Expert Dr. Menka Gupta* to Interpret Your Test Results
- Personalised Plan Based on Your Results: Antimicrobial Protocol, Nutrition, Supplements, and Lifestyle Strategies
- Preferential Access to Premium Pharmaceutical Grade Supplements
- Hassle-Free Kit Delivery & Complimentary Express Shipping (at-home format) or full on-site support (in-clinic format)
- Discounted Access to NutraNourish Health Programs
- Detailed Guidance and Support in Sample Collection & Shipping
- Reintroduction and Re-testing Guidance to Confirm Resolution
SIBO Breath Test Procedure
The SIBO breath test is a simple, non-invasive test available in two formats: at-home (with a kit delivered to your door) or in-clinic (collected at our Singapore clinic with our team supervising). Both formats use the same preparation protocol, the same lab analysis, and deliver the same accuracy of results. Accurate results depend heavily on following the preparation steps precisely. Diet, fasting duration, and supplement washout all directly affect the readings.
Choosing Between At-Home and In-Clinic Testing
Both formats deliver the same diagnostic test and the same lab-analysed results. The choice comes down to convenience and preference:
📦
At-Home Testing
Ideal if you prefer privacy, want to avoid travelling to a clinic for 3 hours, and are comfortable following the test instructions independently. A complete kit is delivered to your door with everything you need.
🏥
In-Clinic Testing
Ideal if you would rather have our Singapore-based team guide you through each step, want hands-on support during the 2–3 hour test window, or prefer that we handle all sample labelling, storage, and shipping on your behalf.
Our team will help you choose the right format based on your preference during your initial discussion.
How Long Does a SIBO Test Take?
The test is completed over a 2–3 hour window. It involves four clear stages and the prep stage is the one that determines accuracy, regardless of which format you choose.
Before the Test (same for both formats)
- Two weeks before: stop probiotics.
- 1–4 weeks before: review all medications with your doctor.
- 24 hours before: restricted diet of plain proteins, white rice, clear broth, water only. No fermentable foods, fibre, fruits, vegetables, sweeteners, or dairy. Stop laxatives.
- 12 hours before: complete fasting — water only.
- 1 hour before: no smoking, gum, or mouthwash.
During the Test (Sample Collection)
After the Test
What Happens Next
The lab analyses your samples for hydrogen, methane, and (where indicated) H2S levels at each time point. Results typically take 1–3 weeks. Dr. Menka Gupta personally reviews your results and walks you through them in your 1-hour consultation. You receive your personalised antimicrobial, dietary, and motility assessment plan.
Your Complete Report
What Will a SIBO Test Tell Me?
The SIBO breath test measures three key gases: hydrogen (H2), methane (CH4), and hydrogen sulphide (H2S) produced by bacterial fermentation in your small intestine. The pattern of gas production and the timing of any rise reveal both whether SIBO is present and what type you have.
Your report covers:
These insights are then translated by Dr. Menka Gupta into a clear, actionable plan for antimicrobial selection, dietary strategy, motility support, and supplement protocol matched to your specific SIBO type.
Program Inclusions
What You Get / Kit Inclusions with the SIBO Test
Why Choose NutraNourish for Your SIBO Breath Test?
- IFM-Certified Functional Medicine expertise: Your results are interpreted by Dr. Menka Gupta, the first Institute for Functional Medicine Certified Practitioner (IFMCP) in South Asia, with 25+ years of clinical experience and 5,000+ patients helped.
- Deep Understanding of Gut Architecture Helping SIBO requires more than reading a positive or negative result. It requires expert understanding of small intestine anatomy, motility, and the upstream drivers of overgrowth which is what guides assessment selection.
- Right Substrate, Right Test We don’t run a one-size-fits-all SIBO test. Dr. Menka selects glucose, lactulose, or both and includes H2S testing where indicated based on your specific symptom pattern.
- Flexible At-Home or In-Clinic Testing: Choose the format that suits your lifestyle. Both deliver the same analysed results and the same accuracy, but the experience is yours to pick.
- Root-Cause Approach, Not Just Antibiotics SIBO assessment without addressing motility, acid production, or structural drivers leads to relapse. Our protocols target the overgrowth and the underlying reason it developed so it doesn’t keep coming back.
- Personalised Antimicrobial Selection Methane-, hydrogen-, and H2S-dominant SIBO each respond to different antimicrobial protocols. Your program is matched to your specific SIBO type, not a generic prescription.
- Re-testing Built Into the Plan We don’t just do the protocol and hope. We sometimes retest to confirm the overgrowth has cleared and to guide reintroduction without flare-ups.
- Phone and Email Support Throughout You’ll have access to ongoing phone and email support during prep, testing, and assessment for any questions or follow-ups.
- Trusted for Accuracy, Transparency & Service NutraNourish has built a reputation for clinical accuracy, transparent processes, and prompt service across Singapore and beyond.
Start uncovering what's really going on inside your gut
Book your SIBO Breath Test today.
What Our Customers Say
Frequently Asked Questions (FAQ)
What do I do if I eat something not allowed in the food test 24 hours prior to taking the test?
Rescheduling your appointment if you can eat restricted foods during the 24-hour prep window will affect your readings and produce inaccurate results. Following the preparation instructions closely is essential for an accurate SIBO diagnosis.
Should I choose at-home or in-clinic testing?
Both formats use the same diagnostic test, the same analysis, and deliver the same accuracy of results. At-home testing is best if you prefer privacy, want to avoid travel, and are comfortable following the test instructions on your own. In-clinic testing is best if you would rather have our team guide you through every step, want support during the 2–3 hour test window, or prefer that we handle all sample logistics on your behalf. Our team will help you choose the right option for your situation during your initial discussion.
Why does my bloating and pain feel worse while taking the test?
The substrate (glucose or lactulose) you drink during the test actually feeds the bacteria being tested for, causing a temporary increase in gas production which can intensify bloating and discomfort. Symptoms typically settle once the test is complete; drink plenty of water afterwards to help things move through.
Is it necessary to stop supplements/medication prior to the SIBO test?
Yes certain medications and supplements need to be stopped 1–4 weeks before a SIBO breath test to avoid inaccurate results. Probiotics, antibiotics, antifungals, and some motility agents can all interfere with readings. We recommend reviewing your full medication and supplement list with Dr. Menka or her team before your test for tailored guidance.
How long will my SIBO breath sample remain stable in the test tube prior to mailing?
Your SIBO breath samples remain stable in the collection tubes for up to ten days, provided they’re kept cool and sealed. That said, we recommend posting them as soon as possible after collection. If you have chosen in-clinic testing, our team handles all sample handling and shipping on your behalf.
What is the number one cause of SIBO?
Impaired gut motility is the most common driver medications or medical conditions that slow the migrating motor complex (MMC) allowing bacteria to stagnate and overgrow in the small intestine. Common contributors include long-term PPI use, opioids, diabetes, hypothyroidism, and post-infectious motility dysfunction.
Is SIBO going to resolve on its own?
Unlikely. The underlying cause of the overgrowth is low stomach acid, slow motility, and structural issues typically remain in place. Working on the overgrowth directly and addressing the root cause is the reliable path to lasting resolution.
Are there other symptoms caused by SIBO that are outside my digestive tract (e.g., brain fog, skin rashes)?
Yes. SIBO can produce symptoms well beyond the gut. Malabsorption of nutrients like Vitamin B12, fat-soluble vitamins, and essential fatty acids contributes to neurological symptoms (brain fog, fatigue, tingling) and skin issues (rashes, eczema). Bacterial metabolites and chronic low-grade inflammation can also influence mood, cognition, and overall skin health.
📚 References (15 sources)
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