FAQ

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.

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

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

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 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.

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.

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.

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.

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.

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.

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. Here is a small guide to follow:

Vegetarian & Vegan-Friendly foods you can eat:

✅ Plain Tofu (unseasoned, not marinated)

✅ White Rice (plain, no seasoning)

✅ Zucchini (peeled, well-cooked)

✅ Carrots (peeled, well-cooked)

✅ Potatoes (peeled, boiled or baked plain)

✅ Small amounts of oil (olive oil, coconut oil)

Quick Sample Meal Ideas

Steamed zucchini and carrots with a drizzle of olive oil

Plain white rice with tofu

Baked peeled potato with a small amount of coconut oil

Herbal tea or black coffee (no creamers or sweeteners)

Important Notes

Keep meals simple — avoid sauces, seasonings, and spices that could interfere with the test.

Stick to low-residue, low-fiber foods — the goal is to minimize any fermentation in the gut.

No snacking or grazing — stick to clear, light meals.

12-hour fast before the test — water only!

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.

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.

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.

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.

Avoid Completely!

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.