Excess bacteria in the upper part of the digestive tract produces gas via fermentation of dietary sugars and starches, that can then lead to symptoms such as bloating, flatulence, abdominal discomfort and nausea, as well as constipation or diarrhoea. SIBO is found to be present in 70% of IBS patients and the build-up of gas in the intestines can be triggered by easily fermentable foods e.g. high FODMAP foods, refined carbohydrates and sugars; by foods which are hard to digest, such as grains, dairy, meat or raw food; and also by insufficient chewing, stress, or over-eating.
The SIBO breath test checks for the production of hydrogen and methane gases, indicating if bacteria have overgrown in in the small intestine, where they are not usually found in large numbers. The results will help to tailor your nutrition programme, according to which type of gas is being produced and usually in conjunction with a stool test, which analyses the health of the colon, or large intestine (see Complete Microbiome Stool Test above).
How to complete the SIBO Test
The SIBO breath test can be completed any day of the week, but requires you to follow specific dietary guidelines for one day beforehand (2 days if you are constipated and do not have a daily bowel movement). After following the restricted diet, you must fast overnight for at least 12 hours before testing. The aim of the diet is to clear any residual fibre from your gut (hence white rice and no fruit, vegetables, nuts or seeds on the menu) and then when you drink the lactulose solution, which is an indigestible fibre, you gain an accurate picture of whether the fibre is fermented by bacteria in your small intestine.
Do not complete the test if you have taken antibiotics or had a colonoscopy within the past 4 weeks. Continue with any prescription medication, but avoid taking any kind of digestive support products such as digestive enzymes, or any other supplements for at least 3 days before testing. Probiotics and antimicrobial supplements, such as those containing berberine or oregano, should be avoided for at least 1 week.
The test takes 3 hours, so set aside a quiet morning to complete it. Brush your teeth as soon as you wake and do not eat or drink anything other than water for the duration of the test. Prepare the lactulose drink by mixing the entire bottle of lactulose with 300ml water, but DO NOT DRINK IT YET.
Prepare the sticky labels by completing your name, the date, the sample number and ticking SIBO. All you need to add, as you proceed through the test, is the time that each sample is collected, before attaching a sticker to each completed glass tube.
- One hour after waking, collect baseline breath sample #00 (see test kit instructions for diagram of how to complete breath samples, by inserting the test tube into the needle holder, while you are exhaling gently into the mouthpiece). Label the tube.
- Rinse your mouth out with the mouthwash provided and collect the second baseline breath sample #0 immediately – the first two baseline samples need to be taken within 1 to 2 minutes of each other. Label the tube.
- Immediately after collecting the second baseline sample, drink the 300ml lactulose/water solution and then set a timer for 20 minutes. Please avoid drinking any fluids for the next 90 minutes, if possible (ideally until after collecting sample #4).
- After 20 minutes, collect breath sample #1 and continue to collect samples #2 to #9 at 20 minute intervals until you have filled all 11 glass collection tubes, labelling them as you go.
Please note down any symptoms that you experience during testing on the test requisition form, which needs to be returned along with the samples. Place glass tubes in bubble wrap envelopes provided, then put back into the cardboard box, with some scrunched up paper to stop them rattling around and send using the pre-paid courier bag. This test is sent via Courier Post so you can arrange for a collection from your home or work address, or drop at a Post Shop.