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The Five Must-Knows for Treating SIBO
that have helped every person I've worked with.

The goal with a SIBO breath test is to identify an overgrowth of microbes in the small intestine, by measuring the production of hydrogen and, or, methane production in response to the sugar solution that is swallowed at the start of the test. The two sugar solutions that are used with SIBO breath testing are glucose and lactulose. Many times I have heard patients voice concern over using a lactulose breath test when they are lactose intolerant. Let me clear this up and share with you some tips for getting the ‘cleanest’ SIBO breath test results.

The two sugar substrates used with these tests are lactulose and glucose. I prefer the lactulose three hour test. Lactulose is a synthetic sugar that is made in the lab. It is not digested or absorbed by human cells and that is why this is used – so it travels the length of the small intestine and makes its way into the colon. It is not lactose. Having a lactose intolerance does not exclude you from taking this test. If you have a lactose allergy, then you should not take this test. True lactose allergies make up a very, very small subset of the population. Again, you can absolutely take this test if you have lactose intolerance. A lactose intolerance will also not effect the test results.

Let’s Recap:

  1. Lactulose is not lactose.
  2. Lactulose is a synthetic sugar that is manufactured in the lab.
  3. It is used because it is not digested and absorbed by human cells.
  4. A lactose intolerance has nothing to do with whether you should or shouldn’t do a lactulose breath test, nor will it interfere with the test results.

It is pretty fascinating if you think about how this test works. I ingest a sugar solution, and then breathe into a tube at twenty minute increments. The microbes that are in my small intestine ingest the sugar, and release gas as a byproduct. The gas builds up in my small intestine and passes through the lining into my blood stream, which then circulates in my body and the gas is exchanged through my lungs and expelled out into my breath, where we can measure gas production. Gas production is measured in parts per million at baseline (the start of the test) and then in twenty minute increments during the ninety minute or three hour test.

"How to Get Most Accurate SIBO Breath Test Post SIBO Guru"

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A test is positive if there is a greater than 15 ppm (parts per million) rise in hydrogen over baseline, a greater than 3 ppm rise in methane over baseline, or a combination of hydrogen and methane rise of greater than 12 ppm over baseline.

What we are also looking for is a double peak of hydrogen and, or, methane – once when the sugar substrate hits SIBO microbes in the small intestine (often by the 90-120 minute mark) and a second when it enters the colon and the large numbers of microbes in the colon consume the sugar substrate and produce gas.

When I review SIBO breath tests, a good majority of these have a high baseline of or methane. This still may be considered a positive test, if the patient has been fully compliant with the test prep instructions. But, what we would rather see is a very minimal gas production at baseline to then compare the rise in hydrogen and methane as the sugar substrate moves along the small intestine.

I also prefer Quintron and CommonWealth Labs for this test, since they also measure CO2 levels with each vial. This measure tells us whether the test interval was collected correctly or not.

Obviously everybody wants to have their test results be as accurate as possible. The test prep instructions are meant to greatly reduce the fermentable load from supplements, medications, food and drink, and to minimize any exposures, like poor oral health hygiene, that will skew the test results. This also means trying to minimize gas production at baseline.

My post today offers some suggestions to minimize a high baseline reading on your SIBO breath test. Let’s first talk about what you will be doing to prep for the test.

When prepping for the test (whether you are using the SIBO Breath test with glucose or lactulose as the sugar substrate) it is imperative that you follow the patient preparation guidelines that are offered by the test provider.

These instructions often include:
1. No smoking, or being around second hand smoke, the day of the test.
2. That you brush your teeth prior to the test and use good oral hygiene practices (this reduces the number of microbes in your mouth that may compromise the test results)
3. No sleeping an hour prior to the test or vigorous exercise the day of the test.
4. That you wait 14 days post antibiotic treatment, a barium study, use of an enema or colonoscopy and that you wait at least 7 days post PPI – or, proton pump inhibitor use, prior to starting the breath test.

The day prior to the test you will be instructed to prep for the test by limiting your diet to only a few ‘prescribed’ LOW fermentable foods, these often include chicken, fish or turkey, white bread, white rice, eggs and clear broth.

If you are offered further advice on the preparation of your test, please adhere fully to these instructions.

Here are a few additional suggestions to prepare for your test:

1. If you consume clear broth, make sure that this was not prepared with fermentable vegetables like garlic, onion, mushrooms or celery. Even though this is a clear broth and you are not consuming the actual vegetable, the fermentable compounds in these vegetables are water soluble. These will leach out into the liquid and likely cause a symptom reaction and they may skew the test results.
2. Use a brand new tooth brush the morning of the test
3. Use a mouthwash with a 3% hydrogen peroxide solution, mixed with equal parts water and swish for two minutes prior to starting the test (Do this prior to starting the test; do not repeat during the test).
4. At the time of the test, if you are experiencing constipation (meaning that you’ve gone multiple days without having a bowel movement) consider doing the food test prep for two days to further reduce the fecal matter that is in your colon, which will reduce colonic fermentation (which can also skew test results)

Lactulose is considered a controlled substance and is only available through a prescription. If you are having a hard time getting a three hour lactulose breath test, I recommend visiting CommonWealth Labs website Your doctor does not need to have an account with this lab. All they need to do is to fax the requisition to CommonWealth. CommonWealth mails the kit to your doctor. You would pick the kit up, perform this test at home and then send the test kit in with your payment. I recommend that you fill out the requisition and give this to your doctor. All they will need to do is to sign it and fax it.

Angela Pifer | Functional Medicine Nutritionist

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from 12 people

Angela Pifer

Good Morning Donna - If it is a true allergy and not a sensitivity, then there is caution with the lactulose test. Lactulose is a man made sugar, yet there are reports (single cases) where reactions from lactulose were thought to be connected to true milk allergy. If you have a lactose intolerance, you can definitely do this test. Warmly, Angela

Angela Pifer


Can someone with a milk allergy take the Lactulose SIBO test?


Angela Pifer

I recommend stopping at least 4 days prior. Anything that will increase transit time (as both of these will - the cause an osmotic shift, drawing water into the bowels) will skew the test results. You can try topical magnesium, castor oil packs, massage, hydration, a rebounder (helps to get the lymphs moving). If you get really constipated prior to the test, then do a two day food prep and not one.. this will help clear out more large intestine fecal matter (to reduce colonic fermentation).

Angela Pifer


Hi Angela,
What is your opinion about taking Magnesium/vita C before a breath test? Some labs say stop 1 day before test others say a week. One said to take. Laxative if constipated before taking the test. I stopped my magnesium 5 days before the test and was miserably constipated.
Amber B

Amber B

Angela Pifer

Hi Chad,
It contains galactose, which is a different sugar. It also contains very little of this. I do not see people with lactose issue (unless a lactose allergy, which is very rare) have an issue taking this. Yes, they will still likely get an upset stomach and gas, but it is shorter lived and manageable.


Angela Pifer


The lactulose solution contains lactose in it. I read the solution ingredients for myself this morning. Lactulose, Fructose, lactose and something else. The solution at Dr.Pimentals office contained lactose as well... so a reaction would happen being allergic to dairy or lactose intolerant.



Juan, I really really appreciate your comment. Thank you. This idea that eating meat - nothing but fat and protein in order to achieve long-term health (in an attempt to "starve" out bad bugs is an interesting theory), but intuitively it does not feel right to me and I believe will pass as a failed theory in the future when our science and studies improve. I have mild SIBO but my symptoms have been severe. My functional med. doc says more meat, less fruit, but I have found a breakthrough that I may have been enzyme deficient this whole time. Even when I was eating lots of eggs and meat, I may have been eating pure fat and protein and living (barely), but I was not vitally healthy; I did not feel well. Well lo and behold I started intaking a lot more enzyme-rich fruits i.e. avocado, grapefruit, apple cider vinegar, and eating lots and lots and lots of lightly steamed leafy green veg (chard, kale) with it, with some nuts, seeds, and just a bit of starch/protein and I already feel a lot better. I am convinced that SIBO has something to do with enzymes and that a combination of fruit/veggie, as you have pointed out Juan, provides the necessary sugars AND fibrous material to keep us satisfied and our bowels flowing well. I thank you Juan for confirming my intuitions, and I want anyone reading this to consider transition more over to a natural, enzyme-rich fruit/veggie diet if paleo has not been working for you. And docs, please consider following this common-sense approach to a more natural diet. SIBO is not fun, and I hope that we eradicate this physical disease of ignorance with nourishing, vitalizing foods. As someone who has studied the pitfalls of both veganism and paleo, I can say I have seen both sides; but there is truly something to be said for seeing yourself as part of Nature and attuning yourself with that. I believe in attunement with that we can find the answers in our own intuition and in discussing that amongst ourselves as well as experimenting as Juan and I have done. Best wishes to all.



Why does it seem that no one can possibly fatohm that we may have caused our own IBS by eating an unnatural diet? Look at Bonobo Chimps, fruit and veggies make up 95% of the diet and 5% comes from bugs, bark, seeds, and rarely raw meat. Our diestive tract is identical to that of the Bonobo Chimp to the point that Dr's cannot distinguish man from chimp during a colonoscopy. If we ate this type of diet as almost all apes do to some variety we would be unlikely to have many of the dis' ease (meaning the body is not at ease. Doctors love to create names for general conditions and due to allopathic treating only of symptoms they fail to ever look at the cause.SIBO is very real as is Candida, ask any microbiologist. If we continue eating foods we weren;t meant to like grains or any foods that has to be heated as it becomes dead, without enzymes, etc Every carnivore on eart sweats through the tongue, eat live whole animals including the blood, bone and guts raw. They have intestinal tracts the length of their bodies. Do the research and you will see we are genetically herbivores, fruits and greens with small amounts of other foods sources like the Bonobo Chimp. While just eating fruit might cause bacterial proliferation, all apes follow it up with eating leafy greens which act as a nutural scrub brush pushing out bacteria. The fruit provides needed calories as the body will convert even a complete atkins style diet into glucose as without it, you will die. Cooking food is the same as sticking your hand in boiling water see how that goes. Eat lots of meat and you deal with putrefaction or bacteria that cause decomposition. If you keep taking in no fiber with that, those bacteria won't be going anywhere. What doctor is going to tell me that fruits and veggies are not essential for optimum health?? We can control symptoms by eating just meat but that does not by itself solve the dysbiosis that exists.No other animal is foolish enough to drink milk after infancy, let alone another animals milk and then to pasteurize it killing anything good it may have. The arrogance of man is unreal. We keep tampering with nature and wonder why we are ill.Now before anyone gets super offended, I did an Atkins style diet for 10 years to avoid drugs after over 35 hospital visits in my life. I have suffered from IBS/Crohns since the age of 5 and am now 38. I have often followed doctors advice like gospel without ever doing enough of my own due diligence. I know how I am supposed to have been eating and what I need to work on getting back to which is a fruit and veggie diet with small amounts of protein and fats. Most people are unaware that fruits and veggies have protein and fats and you will not find heart disease, cancer, high blood pressure in natural animals. Now onto the second topic which is what do people like me do when we were raised on food that harmed us, made us ill, often are treated with antibiotics which while effective at kiling off good and bad flora, if we go back to eating the wrong foods like grains (I dare anyone to try and eat raw uncooked grains in nature) we get a recurrence of the symptoms often worse than it started.What do they call it when you do the same thing over and over expecting a different result???The real key is how to create remission and clean out as many negative microforms as possible, then create a transitional diet until we can make our way back to nature's intended foods. Fruits need no sauces, no artificial sweetener and we all crave sugars, its natural and our hands and its lack on needed preparation makes it the ideal food. For many including me, I want to know how to get my intestinal flora to be balanced enough to eat a banana without feeling intoxicated and getting bloody or mucous in my stools.While it is true we can live on meat alone, we are not nearly as vibrant as we should be. We are forcing our bodies to be overly acidic non stop which is definitely not optimum health. I did it and while yes I was functional and appeared healthy for a while, my health was eroding slowly and I was aging quickly due to an accelerated level of oxidation in my body.We assume our ancestors hunted but did they all really hunt that often, or only when they couldn't find enough fruit for calories to sustain themselves? Do we think nature intended us to need to create tools to hunt, factories to process grains? Why do we need to eat grains with sauces, toppings, and why would nature want us to be able to overeat them so easily?? Would you have chased wild cattle before farms to milk them in the wild?? Are we all chronically dehydrated no matter how much water we force ourselves to drink unlike people or apes that eat a fruit rich diet? Are there any fructose intolerant apes?? I am pretty certain we would see health problems arise with many years of taking apes and making them eat meat, dairy from cows, you get the idea and it shows us how silly we can be. It is pretty hard to overeat a diet made up of 90-95% fruits and veggies. Fruits have energy, vitamins and minerals, are water rich and are great sources of calories. Veggies are even more nutrient dense and serve to mineralize and alkalize our bodies as our blood is slightly alkaline, eating all acidic foods like meats will force the body to leach minerals to maintain the blood Ph. This is why supplementing calcium has not solved osteoporosis.My quandry is how do we transition from being very ill individuals to the omnivores that all our natural bretheren are??We know we need to kill off bacteria where it doesn't belong and try to swing back the balance towards the proper microbes that should co-exist. I would think it would be a combination of using antibiotics first, then using a slow transitional diet that over time would allow us to get to our best natural diet.Perhaps antibiotics with a protein and fat diet to start? Then add in leafy greens? Then add in one piece of fruit, then two, until we convert out diet to one where we look and feel great and all these issues, IBS, lupus, and tons of others that all have the leaky gut in common.What we have done in the past has not solved it, prhaps its time for a new approach, a combination of modern day medicine and a transition to a healthy diet over time.I have no moral dilemma with eating meats as I would eat cow dung if I knew it would allow me to feel good. In nature animals eat based first on desire, second on availability of food supply.Animals don't have to worry about things like food combining as they don't mix and match as we do, nor do they cook and kill the essential enzymes necessary for life. Cooked food is dead food. Apes, monkees and chimps will eat meat if and when they have to, as we all have a survival instinct, but this does not mean we were intended to eat this way. I don't want to be a frozen eskimo and go study and you will find out they have very short lifespans.We need to fix those of us who are already broken and help those who are just starting out to avoid the same mistakes we made.I welcome any and all feedback


Angela Pifer

Hi Mary,

I answer this specific question in the second paragraph - please look again. And, to clarify, being lactulose intolerant will not affect the results. What patient are more concerned about is that if they are lactose intolerant and experience very debilitating symptoms when the consume lactose - that if they take consume a vial of lactulose for this test, that they will experience dramatic gut symptoms as a result. No, they will not (specific to lactose intolerance) and if lactulose intolerant, this will not affect the test procedures or results.

Many people note symptoms when doing this test. This is a population that already has a sensitive gut. I recommend that my patients consume activated charcoal after they complete the last breath test interval. This helps to bind some of the fermentable compounds and reduces the level of symptoms that the patient experiences.



Angela Pifer



I don't see in this column where it says being lactose-intolerant affect the reults or not. The headline seems a bit misleading...


Angela Pifer

Hi Mary Ann,

If positive, I would work with a qualified practitioner to determine the best treatment plan and protocol to get you healed.


Angela Pifer


What can be done if I test positive on the SIBO test?

Mary Ann Siehr

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