FAQ2

What is the Prep Diet?
Click here for the prep guide. The SIBO breath test involves a 24-48 hour prep diet. This means 24-48 hours prior to your test.
Some practitioners may suggest a longer prep depending on how fast your intestinal tract moves along i.e. constipation. However, that is something you would have to discuss with your practitioner OR you can email SIBO CLINIC CANADA at info@sibocliniccanada.com for help.
During this prep, stop taking all non-essential medications, supplements, and probiotics. This includes over the counter pain medications, allergy medications, and antacids. If you don’t know what medication is considered essential, consult your prescribing physician. The goal is to starve the bacteria for a day in order to produce the best results when doing the test. Bacteria fuel on plant products and sugars, so the only foods that you can have on the prep diet are listed here – if it is not on this list DO NOT eat it:
- Any meat/poultry/fish/seafood that is not cured or brined
- Plain, steamed white rice
- Eggs
- Clear meat broth (made only from the meat, no bone/cartilage or vegetables)
- Fats/oils (coconut/olive/vegetable oils, butter, or lard)
- Salt and Pepper (no other herbs/spices)
- Weak black coffee and/or weak black tea (plain, no sweeteners or cream, NO green or herbal teas)
- Plain water (no mineral water or water with additives)
- Vegans or vegetarians can add a little tofu or soak lentils
The prep diet is incredibly restrictive. I really can’t replace things on it?
No. Any changes to the diet can affect the results of the test. The manufacturer of the SIBO test created the prep diet based on their research and testing. Only the things on the prep diet are allowed to get the cleanest results for the SIBO test.
Do I have to eat everything on the prep diet?
No. If you do not eat grains, for example, do not consume the rice. If you do not eat eggs, then do not start just for this diet. Eat things on this list, but only of what you would normally eat.
Can I eat cheese on the prep diet?
Many practitioners may will modify your diet to what they feel is the best test for you. We at SIBO CLINIC CANADA only go by what the manufacturer of the SIBO test (Qiuntron) has worked with to create the guidelines for the test. If your practitioner has a specific modification (such as hard cheeses) then you must discuss it with them, as we cannot give advice about foods outside of the manufacturer’s guidelines. However, although cheese is a form of dairy, and dairy is not on the list of foods to consume because of the lactose-containing sugar, hard aged cheeses have minute traces of lactose, and the more aged the cheese, the less lactose it contains. If you do find the prep diet far too constrictive, and feel the need to have cheese, please proceed with caution and make sure the cheese is non-processed aged cheese.
Can I eat brown rice/quinoa/etc?
The only grain acceptable on the prep diet is plain, white Basmati or Jasmine rice because they have the lowest glycemic index of all rice). Other rice/grains have a higher level of fiber and macromolecules that SIBO bacteria like to eat. Any substitutions can give inaccurate test results. If you normally do not eat rice, do not eat any during the prep diet.
What if I’m a vegetarian/vegan?
The SIBO prep diet specifically cuts out plant products and sugars in order to starve the bacteria for a day prior to taking the test, which will give you the most accurate results. If you do not adhere to the diet, the bacteria may not react during the test, leading to possible false negative results. If you do not normally consume poultry/meat/eggs, please consult with nutritional expert to determine your options.
Why is the meat broth so specific on the prep diet?
Regular bone broth is often cooked with cartilaginous bones or meat. When cooked, polysaccharides (specifically glucosaminoglycans or GAGs) from the cartilage leech into the bone broth and can feed a bacterial overgrowth and therefore be problematic for people with SIBO.
It is important that if you consume meat broth for the prep diet, it must be made from ONLY the meat. There cannot be any bone or cartilage included, and it cannot have any vegetables or herbs (aside from salt and pepper) in it. Most store bought broths have ingredients that are not appropriate for this prep diet, so homemade broth is the best decision.
Can I eat cured meats/lox/sausage?
Any meat ingested must be made without any added sugars/brines/cures/etc. to avoid contaminating the prep diet. Avoid meats like deli-meat, lox, and pre-prepared meats that have any other herbs and spices besides salt and pepper. Meats like sausage usually have other herbs or sugars in them and should be avoided during the prep diet.
Can I eat sushi?
The sashimi fish is fine on the prep diet, when eaten alone and without sauce. The rice in Nigiri is usually made with sugar-based binders to make it stick together better, and thus should be avoided on the prep diet. The only exception is home-made Nigiri with steamed white rice and no sauces. Sushi rolls are very much to be avoided.
What about smoking/alcohol?
If you are a smoker, of tobacco or cannabis, there is no recommendation to stop use during the prep diet. However, do not smoke anything for at least one hour prior to taking the breath test, or during the time of the test (4 hours total). If you ingest cannabis in edible form, it must be avoided during the prep diet. Smokeless tobacco (chew) should be avoided during the prep diet and prior to the test as well. Avoid all alcohol during the prep diet.
Hydrogen Sulfide (H2S) testing?
We don't test for Hydrogen sulfide yet. It is coming soon. However, please read the following information of what we see as current
1. Cost: H2S SIBO testing can be more expensive than traditional hydrogen and methane SIBO testing. The cost can vary depending on the specific test and the laboratory. The higher price might concern individuals trying to manage their healthcare expenses.
2. Accuracy: H2S SIBO testing methods are still evolving, and accuracy and reliability may have limitations. Some tests have a higher false positive or false negative rate than hydrogen and methane testing. This can make it challenging to diagnose H2S SIBO based solely on testing results confidently.
3. Drawbacks of H2S Testing:
- Limited Research: Compared to hydrogen and methane SIBO, more research and clinical experience with H2S SIBO needs to be done. This can make it harder to interpret the results and understand the implications of a positive or negative test.
- Interpretation Challenges: Interpreting H2S SIBO test results can be more complex. Various bacterial strains can produce different levels of H2S, and the significance of those levels can sometimes be clarified. This complexity can lead to uncertainty in treatment decisions.
- False Positives/Negatives: As mentioned earlier, accuracy can be a concern. False positives and negatives can lead to misdiagnosis or delay appropriate treatment.
- Treatment Approach: The treatment approach for H2S SIBO might differ from traditional hydrogen and methane SIBO. However, due to the evolving nature of H2S testing and limited clinical guidelines, healthcare practitioners might have varying approaches to treatment.
- Established Methods: Hydrogen and methane SIBO testing methods have been used longer and are more commonly found in clinical practice.
- Clearer Guidelines: Treatment protocols for hydrogen and methane SIBO are better defined due to the larger body of research and clinical experience.
- Cost: Hydrogen and methane testing is generally more cost-effective, making it more accessible for individuals.
In summary, while H2S SIBO testing might offer valuable insights into certain cases, some challenges and uncertainties are currently associated with its use. If you're considering SIBO testing, discussing your options with a healthcare practitioner knowledgeable about SIBO and the available testing methods may be a good idea. They can help you decide based on your specific symptoms, medical history, and each testing approach's potential benefits and drawbacks.
Collapsible content
What is SIBO?
Small Intestinal Bacterial Overgrowth (SIBO) is a condition where excessive bacteria build up in the small intestine — a section of the digestive tract that’s normally low in bacterial population.
The small intestine is crucial for breaking down food and absorbing nutrients. But when bacteria from the large intestine migrate upward, or when conditions like sluggish motility or low stomach acid reduce our natural defenses, things start to go sideways. Low stomach acid, in particular, is a major factor — it’s your first line of defense against invaders, and without enough of it, bacteria have a much easier time setting up shop where they don’t belong.
Even more surprising? Excessive social media use has been linked to disrupted vagus nerve function — the very nerve responsible for gut-brain communication and healthy motility. In today’s high-stimulus digital world, nervous system dysregulation could be another hidden contributor to SIBO.
The result? Food ferments in the wrong part of the gut, triggering symptoms like bloating, gas, abdominal cramps, and unpredictable bowel movements.
In fact, up to 80% of people diagnosed with Irritable Bowel Syndrome (IBS) may actually have undiagnosed SIBO — making it a far more common (and overlooked) root cause of digestive distress than most realize.
What are some common triggers or root causes of SIBO?
Low or no stomach acid
Excessive social media use
Pancreatic enzyme and/or bile insufficiency
Hypothyroidism/Hashimottos
Chronic stress
Infections (viral/bacterial/parasitic)
Chronic constipation
GI tract dysfunction (ileocecal valve)
Nerve dysfunction
What symptoms are commonly associated with SIBO?
Bloating (especially after meals — that “six-months-pregnant” feeling)
Gas and belching
Abdominal discomfort or cramping
Diarrhea, constipation, or a mix of both
Fatigue (bacteria compete with you for nutrients, leaving you drained)
Brain fog and difficulty concentrating
Food intolerances, especially to carbs and fermentable fibers (FODMAPs)
Nutrient deficiencies (like B12, iron, and fat-soluble vitamins)
Unintended weight loss or weight gain
Skin issues like acne or rosacea
How can SIBO impact your health?
SIBO (Small Intestinal Bacterial Overgrowth) doesn’t just cause digestive discomfort — it can have a ripple effect throughout the entire body.
When bacteria overgrow in the small intestine, they interfere with how you digest food, absorb nutrients, and regulate immune and nervous system function. Over time, this disruption can contribute to or worsen a wide range of conditions, including:
Alzheimer’s and Parkinson’s disease
Multiple Sclerosis
Type 2 diabetes and high blood pressure
Autoimmune diseases
Fibromyalgia and Chronic
Fatigue Syndrome
Irritable Bowel Syndrome (IBS)
Acid reflux and leaky gut
Brain fog and mood disorders
Restless Leg Syndrome
Acne and skin inflammation
Unwanted weight loss or weight gain
This happens because the bacterial imbalance can lead to chronic inflammation, nutrient deficiencies (like B12, iron, and fat-soluble vitamins), hormonal imbalances, and damage to
the gut lining — all of which impact key systems in the body.
In short: SIBO is not just a gut issue. It can be the hidden root cause of health problems that seem totally unrelated to digestion. Getting it under control can be life-changing — physically, mentally, and emotionally.
Lactulose vs. Glucose Breath Test – What's the Difference?
Lactulose Breath Test
Lactulose is a synthetic sugar that is not absorbed in the small intestine. It travels through the entire small intestine and into the colon. If bacteria are present, they ferment the lactulose and produce hydrogen and methane gases, which are expelled through the breath. This is how SIBO is detected. The test duration for lactulose is typically 3 hours. Because it travels through the full small intestine and into the colon, it can detect overgrowth in both the upper and lower (distal) areas — which is key, as SIBO often occurs in the distal portion.
Glucose Breath Test
Glucose is a simple sugar that is rapidly absorbed in the upper small intestine. If bacteria are present in that upper section, they ferment the glucose and produce gas, which is expelled through the breath. This is how SIBO is detected. The test lasts about 2 hours, if not sooner. Because it’s absorbed quickly, glucose may miss overgrowth in the lower part of the small intestine, where SIBO is more common.
Key Differences:
Absorption & Reach
Glucose: Fast absorption → Best for detecting upper (proximal) SIBO
Lactulose: Travels farther → Detects both upper and lower SIBO
Diagnostic Accuracy
Glucose: May miss distal SIBO
Lactulose: More comprehensive coverage — typically the preferred test
Note: Some practitioners prefer glucose over lactulose for various clinical reasons, while others rely on lactulose for broader coverage. In many cases, the choice also comes down to personal preference or specific testing goals. If you're unsure, check with your practitioner.
What is the prep diet?
The SIBO breath test requires a 24- to 48-hour prep diet before your test. This short-term, low-fermentation diet is essential to help "quiet" the gut and ensure accurate results.
During this time, you'll need to avoid all non-essential medications, supplements, and probiotics — including things like over-the-counter painkillers, allergy meds, and antacids. If you're unsure whether something is essential, it's best to consult your prescribing physician.
The goal of the prep diet is simple: starve the bacteria. Since bacteria feed on plant fibers, sugars, and fermentable foods, this diet cuts off their fuel source so we can better detect any abnormal gas production during the test.
Allowed foods:
Unprocessed meat, poultry, fish, and seafood (not cured, brined, or seasoned)
Plain white rice (Basmati or
Jasmine only)
Eggs
Clear meat broth (no bones,
cartilage, or vegetables)
Fats and oils (butter, coconut
oil, olive oil, vegetable oil, or lard)
Salt and pepper (no added
herbs, garlic, or spice blends)
Weak black coffee (No Tea's, herbal or otherwise)
Plain water (no added minerals
or flavoring)
This isn’t a long-term diet — it's just for the 1–2 days leading up to your breath test. After the prep diet, you'll switch to a 12-hour fast the night before your test, then begin testing
in the morning.
The prep diet is incredibly restrictive. Can I replace foods or make substitutions?
We get it — the prep diet isn’t fun. It’s bland, limited, and restrictive by design. Unfortunately, it’s also non-negotiable if you want an accurate SIBO breath test result.
The reason substitutions aren’t allowed is because even small changes (like switching white rice for brown, or adding a splash of almond milk to coffee) can feed bacteria, interfere with fermentation patterns, and throw off your results.
Think of it like prepping your gut for a clean reading — no extra noise, no hidden variables.
So while it might not be the most exciting 24–48 hours of your life, it’s a temporary sacrifice that sets you up for answers, clarity, and next steps. The good news? It’s over quickly, and you’ll go back to eating normally right after the test.
Hang in there — your gut (and your future self) will thank you.
Do I have to eat everything on the prep diet?
No, you don’t have to eat everything listed on the prep diet — it’s not a checklist. The goal is simply to eat only from the allowed foods, but you don’t need to force anything you wouldn’t normally eat.
For example:
If you don’t eat grains, skip the rice.
If you avoid eggs, don’t add them in just for the prep.
If meat is your go-to, stick with that.
Just choose from the approved options based on your usual
eating preferences. The important part is not what you eat — but what you don’t:
avoid all fermentable foods, plant products, sugars, and anything off-list.
Keep it simple, stick to what works for your body, and you'll be good to go.
Can I eat cheese on the prep diet?
Many practitioners may choose to modify the prep diet based on their own clinical experience. However, we follow only the guidelines developed by QuinTron, the manufacturer of the SIBO breath test. These guidelines are designed to maximize test accuracy — and dairy, including cheese, is not on the approved food list.
That said, some practitioners may allow small amounts of hard, aged cheeses, since they contain very little lactose — and the more aged the cheese, the less fermentable sugar remains.
If your practitioner recommends including hard cheese, that decision is between you and them. We strongly advise against making any food substitutions without medical guidance, as this could compromise the results.
If you find the prep diet too restrictive and are considering cheese on your own, please proceed with caution — and only choose non-processed, aged cheeses (no soft or flavored varieties). But again, for best accuracy, we recommend sticking to the official prep diet as closely as possible.
When in doubt, leave it out.
Can I eat brown rice, quinoa, or other grains on the prep diet?
No — the only grain allowed on the prep diet is plain white Basmati or Jasmine rice. These varieties are recommended because they’re low in fiber, low-residue, and have the lowest glycemic index of all rice types — making them less likely to feed bacteria in the small intestine.
Other grains like brown rice, quinoa, oats, or whole wheat contain more fiber and complex carbohydrates, which SIBO-related bacteria love to ferment. Including them can lead to inaccurate breath test results.
And remember: if you don’t normally eat rice, you
don’t need to add it in just for the prep diet. Simply choose from the other
approved foods that you would typically eat.
Bottom line: stick to the prep list exactly as outlined. Even small substitutions can affect the outcome of your test.
What if I'm a vegetarian or vegan?
The SIBO prep diet is intentionally restrictive — it eliminates plant products, sugars, and fermentable carbohydrates for 24–48 hours prior to testing to help starve the bacteria and get the most accurate results.
For individuals following a vegan or vegetarian diet, this can be challenging — especially since most plant-based foods are high in fiber and fermentable sugars, which can interfere with test accuracy.
If the prep diet is not followed exactly, there’s a risk that bacterial fermentation won’t occur during the test window — leading to false negative results.
If you don’t normally consume meat, poultry, or eggs, we strongly recommend consulting with a qualified nutritionist or your practitioner before the test to determine the safest and most effective approach for your situation.
Bottom line: accurate results depend on strict adherence. If modifications are necessary for ethical or medical reasons, get professional guidance so you can still get meaningful data from your test.
Why is the meat broth so specific on the prep diet?
Great question — and an important one.
Regular bone broth is often made using cartilaginous bones and connective tissue. While that’s great for joint health under normal circumstances, it’s not ideal before a SIBO test. That’s because when bones and cartilage are simmered, they release olysaccharides — specifically glucosaminoglycans
(GAGs) — which can feed bacterial overgrowth and skew your test results.
For the prep diet, broth must be meat-only. That means:
No bones
No cartilage
No skin or connective tissue
No vegetables, herbs, or seasonings (besides salt and pepper)
No store-bought broths unless they meet all of the above criteria — which most do not
Your best option? Make it at home using just meat and water, seasoned lightly with salt and pepper if desired. It’s simple, clean, and won’t interfere with the test.
Can I eat cured meats, lox, or sausage on the prep diet?
No. All meats consumed during the prep diet must be plain and unprocessed, with no added sugars, brines, cures, or seasoning blends.
That means avoiding:
Cured meats (like prosciutto, salami, or bacon)
Lox or smoked fish
Sausages or deli meats (even if labeled “natural” or “organic”)
Any meat with added herbs, garlic, spices, or marinades
Why? Because these extras often contain sugars, preservatives, or fermentable compounds that can feed bacteria and interfere with your test results.
Stick to simple, unseasoned cuts of meat, poultry, or fish — cooked plainly with only salt and pepper. When in doubt, choose fresh over packaged, and skip anything with a label full of ingredients.
Can I eat sushi on the prep diet?
Sashimi — plain raw fish without sauce — is acceptable on the prep diet. However, most other types of sushi should be avoided.
Here’s why:
Nigiri (fish over rice) is typically made with seasoned rice that contains sugar and vinegar — both of which can feed bacteria and compromise test accuracy.
Sushi rolls (maki) often contain vegetables, seaweed, sauces, and added sugars — all of which are off-limits.
The only potential exception is homemade Nigiri made with plain, steamed white Basmati or Jasmine rice and no added ingredients or sauces. Even then, proceed with caution — most sushi-style rice is sticky because of sugar or other additives.
Bottom line: Stick to plain sashimi if you really want sushi-style protein — otherwise, it’s best to skip sushi altogether during the
prep phase.
What about smoking or alcohol during the prep diet?
Avoid Completely!
Do you offer hydrogen sulfide (H₂S) SIBO testing?
Not at this time. Perhaps in the near future.
However, hydrogen sulfide (H₂S) SIBO is a newer subtype of SIBO that’s getting more attention in the research world. While we’re excited to offer H₂S testing in the near future, here’s what we want you to know right now:
Why we haven’t added it yet:
Cost – H₂S testing is currently more expensive than standard hydrogen and methane breath testing. Pricing can vary by lab, and for many people, it’s not yet a cost-effective first step.
Accuracy – H₂S testing methods are still being refined. False positives and false negatives are more common compared to traditional testing, which can make results harder to trust.
Limited research – There’s still a lot we don’t know about H₂S SIBO. With fewer clinical studies and real-world cases, interpreting results — and knowing how to treat them — can be tricky.
Complex interpretation – Different bacterial strains produce varying levels of hydrogen sulfide, and the clinical significance of those levels isn’t always clear. This can lead to uncertainty in diagnosis and treatment.
Treatment protocols are evolving – While there are emerging protocols for H₂S SIBO, they aren’t yet as well-defined as those for hydrogen or methane overgrowth. Practitioner approaches can vary widely.
Why we continue to use hydrogen and methane testing:
It’s cost-effective
It’s widely validated
It comes with clearer treatment guidelines
It has years of clinical research behind it
For now, hydrogen and methane breath testing remains the gold standard — and it’s what we trust to give our clients the most accurate and actionable results.
We’re keeping a close eye on H₂S testing as it evolves, and we’ll be adding it to our offerings as soon as we feel it meets the same high standard we expect for all of our diagnostic tools.