Test for SIBO, fructose intolerance and/or lactose malabsorption or other FODMAPs (such as sorbitol and mannitol) by collecting samples of your breath!
- SIBO (Small Intestinal Bacterial Overgrowth): Ideally three breath tests should be conducted, first using glucose then fructose, then lactulose. Each test substance has different advantages and disadvantages. Best practice is to complete all three tests. Together, this will inform your practitioner of the bacterial role with a higher degree of accuracy.
- Lactose Intolerance: If you are concerned about dairy intolerance, the recommended procedure is to first do a lactulose challenge, followed by lactose.
- Fructose Malabsorption: Commonly associated with IBS, a challenge with fructose can be run after a lactulose challenge.
- Sucrose (sugar) intolerance: Sucrose is common sugar, but also naturally occurs in many fruits and vegetables as well. It can be tested after a lactulose challenge.
- Sorbitol: this is a polyol that occurs naturally in some fruits (such as apples and some berries). It is commonly added to processed foods and as a lower-calorie sweetener in desserts, chewing gum, snack bars and sweets. It can cause digestive distress in those who cannot digest it.
- Mannitol: this is another polyol, found in some fruit and vegetables such as cauliflower, mushrooms, and commonly used in chewing gum, sweets and other processed foods. It can also cause digestive distress in those who cannot digest it.
If testing for lactose intolerance or fructose malabsorption, current breath testing guidelines recommend a lactulose (+/- glucose) challenge be conducted before the lactose or fructose result can be accurately interpreted.
Written instructions for the breath test, including the preparation diet, are here. In brief, you will follow these steps:
- An exclusion period applies after some procedures, medicines and probiotics. See the instructions here.
- Follow a special diet for at least one day (your practitioner may recommend you follow it for longer) before performing the test.
- On the morning of testing ONE HOUR after getting up (no vigorous exercise, eating or smoking allowed), a baseline breath sample is collected
- You’ll have a drink with the provided testing substance (a type of sugar) with a glass of water. You are not permitted to have anything else to drink for the the first hour, then you may drink water only.
- Breath samples are collected every 15-20 minutes for a total of 2.5-3 hours. The exact spacing and number of samples is dependent on the sugar being tested (see videos below).
The current recommended strategy for determining the role of bacterial aberrations in the small bowel, is to conduct 3 separate breath tests. These involve and oral challenge with lactulose, glucose and fructose on separate occasions, as each sugar gives different information. Additional sugars or polyols can be tested as well. Discuss with your health practitioner if these might be suitable for you.
Each substrate is tested on different days, with at least 2 days between. You have to follow the same preparation diet for each test.
What are the Options for Doing the Hydrogen-Methane Breath Test?
You can book to do the breath test in our Auckland clinic, or, using a special kit you can collect breath samples in the convenience of your own home. The test is also suitable for children, as long as they can blow into a bag following instruction to do so.
In-clinic tests are run on weekdays. You will need to arrive at the clinic between 08.30am and 09.30am on the test day, and expect to be at the clinic for at least 3 hours.
How is the Hydrogen-Methane Breath Test Done?
The test is collected in the morning, over about 3-hours (depending on the test sugar), after period of diet preparation.
- The preparatory diet is a one-day strictly restricted diet. This is followed the whole day before testing. Test Preparation instructions are here.
- Fast (water-only) overnight (minimum 12 hours)
- Be awake (no vigorous exercise) for one hour before starting the test. Please go for a gentle walk for 20-30 minutes at this time.
- Collect a baseline breath sample. Conduct a mouthwash (if supplied), then another breath sample.
- Drink the provided substrate, mixed or dissolved in water
- Then, at the specified intervals, you will collect additional breath samples (11 samples in total for glucose & lactulose, 7 or 8 samples for fructose & lactose). Follow the instructions on your paperwork. If you are doing multiple tests (e.g., lactulose & glucose), you will only do the mouthwash once.
Instructions for conducting the Hydrogen-Methane Breath test
We strongly recommend that if this is your first hydrogen-methane breath test for digestive problems, you should complete the “gold trio” of tests. This involves 3 separate tests, with Glucose, Fructose and Lactulose – in that order. These three tests can be conducted with a “rest & diet” day in between, or this can be shortened if you follow the schedule outlined below. You can leave longer between each test if this suits your planning better
Each test takes about 3 hours, after which you can eat and drink normally until resuming the preparation diet the following day for the subsequent test.
Here is an example of how to plan your tests. Before each test you would get up at 8am (latest), go for a gentle walk.
- Sunday: Prep diet all day
- Monday: Do the Glucose challenge test 9am – 12 noon. Resume breath test diet
- Tuesday: Fructose challenge test: 9am – 12 noon. Eat normally for lunch & dinner
- Wednesday: Prep diet.
- Thursday: Lactulose challenge test: 9am – 12 noon. Eat normally thereafter.
Analysis of results from each of these three sugars provides your clinician with the most accurate information regarding bacterial metabolism in your digestive symptoms.
What Will I Need to Conduct the Hydrogen-Methane Breath Test at Home?
You will need:
- One kit for each sugar substrate being tested
- A timer (the one on your cell phone is perfect)
- Water and glass
- Pen
- A 4-hour period for conducting the test (one hour of which is being awake before testing can start)
Everything else is supplied in the test kit. For accurate results, it is crucial that the breath samples are collected correctly, with at least one day between each test. Please watch the videos above and read the instructions in your kit, which explains the procedure. We recommend you watch the video below to ensure you understand the collection procedures. Time intervals may change with different substrates – ensure you read the instructions that come with your kit.
Once your test has been completed, you can eat and drink normally. Package the tubes in the box they came in, place in the pre-paid courier bag provided and either phone the courier to collect or drop in to your local post shop.
If a person is easily confused, overly anxious or for some reason unable to follow instructions or unsure if you can collect the samples correctly, please contact us to book the test at our Auckland lab – an in-clinic test is the preferred option for accurate results.
How do I get the Results of my Hydrogen-Methane Breath Test?
Reports are typically ready within 5-7 working days of them being received at our lab. We will send them to your ordering health professional. If you have self-referred to do the test, please nominate the health professional who will review and discuss your breath test results and to develop a management plan for you. If you do not have a practitioner who is knowledgeable about breath testing, please book and initial appointment with any of our consultants.
You can read more about breath testing here.
Our testing and interpretation protocols are congruent with those outlined in the North American Breath Testing Guidelines (2017) as published in the American Journal of Gastroenterology (PMID28323273), the American College of Gastroenterology Clinical Guideline for breath testing, and have been further refined based on our own research.
Please note: Test results should be delivered in the context of a professional consultation – either in our clinic, online or we can send the results to the registered health consultant you specify.
For more information about the background and science behind the SIBO test, read here or give us a call 09 846 5566
You can also read more about SIBO here
Lactulose and Lactose are used to test different things. Please check you are ordering the correct test.
Samples must reach us within 5 days of collection (a return courier bag is provided). Results are generally completed and sent to your practitioner within 5-7 working days.
Book an in-clinic test by calling us on 09 846 5566
Are you Concerned About Your Digestive Health?
Increasingly, the light is shining upon the important role the digestive system and how the organisms that live there influence many aspects of health. While irritable bowel syndrome (IBS) is a common condition and you may or may not have it, understanding the role of gut bacteria in a digestive problem is now possible.
When bacteria overgrow in the small intestine, “Small Intestinal Bacterial Overgrowth” (SIBO) can occur.
Having excessive bacteria in the small intestine (which is meant to be fairly devout of bacteria), means that food may be fermented there, causing common problems such as:
- Gas (wind)
- Bloating (abdominal distension)
- Pain
- Altered bowel habits (constipation and/or loose stool)
- Feeling unwell after eating – often associated with specific foods.
Who Should do the Hydrogen-Methane Breath Test?
- Gas, bloating, reflux or heartburn
- Abdominal pain
- Constipation or diarrhoea
- People with irritable bowel syndrome (IBS)
- Hypermobility disorders
- Unexplained food malabsorption
- Digestive disturbance after a tummy bug, antibiotics, pain killers or stomach acid-reducing drugs (may also be worse from probiotics, fibre, certain fruit/veges or wholefoods).
- Skin problems (acne, psoriasis, rosacea etc.)
- Body pain or fibromyalgia
- Brain fog or fatigue
- Iron deficiency or gut symptoms when taking iron supplements
- Cognitive dysfunction (poor memory, concentration/brain fog)
- Neurological disorders including Parkinson’s Disease
- Women with endometriosis and digestive problems
- People with intolerance to FODMAPs





Sharon Erdrich (store manager) –
Sorry you found it challenging Diego. We do understand it’s a complicated process for the uninitiated, so our instructions are also on a video and we do offer in-house testing. However, most people navigate sample collection successfully. It’s always good to know the specific challenges people encounter so we can help out or update our process. I hope you got what you need for supporting your health journey.