SIBO Breath Test


What is the SIBO breath test?

A SIBO breath test is a diagnostic tool used to detect small intestinal bacterial overgrowth (SIBO). The SIBO breath test at home involves the patient blowing into a tube to collect air samples at regular intervals over a certain period of time. The collected air samples are then analyzed for the presence of certain gases that are produced by bacteria in the small intestine. The presence of these gases in the collected samples indicates an overgrowth of bacteria in the small intestine, which is an indication of SIBO.

What is small intestinal bowel overgrowth (SIBO)?

SIBO stands for Small Intestinal Bacterial Overgrowth, which is a condition in which excessive and abnormal bacteria growth in the small intestine. This condition is caused when the normal bacteria living in the large intestine migrate to the small intestine. SIBO can lead to a variety of symptoms including bloating, abdominal pain, gas, diarrhea, constipation, and fatigue.

Eliminating certain foods from the diet can be an important part of treating SIBO, as some foods can act as fuel for the bacteria in the small intestine. Foods to avoid include processed foods, refined carbohydrates, and sugary foods. In addition, reducing the amount of fiber in the diet can help to reduce symptoms.

The microbiome is essential for maintaining a healthy balance in the body. It helps to break down food, absorb nutrients, and defend against pathogens. Additionally, it is thought to play a role in regulating the immune system, metabolism, and even mental health.

Research has shown that imbalances in the microbiome can lead to a range of health issues, including digestive disorders, skin conditions, and even chronic diseases. Therefore, understanding the composition of the microbiome and how it can be optimized is essential for overall wellbeing.

How does measuring my breath tell me what is happening in my Intestines?

Measuring the levels of certain compounds in the breath sample, such as hydrogen and methane are the gold standard to measure SIBO. Hydrogen and Methane compounds are produced by the bacteria in the intestine and can help to identify what is happening in the small intestine. The sample is then sent to a laboratory for further analysis, where the types of bacteria present in the sample and their levels can be determined. This information can then be used to determine if there is an imbalance of bacteria in the small intestine indicating SIBO.

Where is the test performed?

The SIBO breath test can be performed in the comfort of your own home. We post the test kit to you. Once you have done the breath test for SIBO, you just need to send back to the lab and they will start the analysis. The analysis takes approximately 14 days.

SIBO Test Instructions

Seven days before the test, one should avoid the use of laxatives, stool softeners, and/or stool bulking agents as well as antacids with aluminium or magnesium hydroxide. Additionally, probiotics should not be consumed in the 24 hours prior to the test. During the 12 hours prior to the test, one may only consume plain water, coffee, and tea (without any additions like sugar, artificial sweeteners, milk, or cream). During this period, no other foods or medications should be taken, and no gum, candy, or mouthwash should be used. Allowed foods for the 12 hours prior to the test include baked or broiled chicken, fish, or turkey (only with salt and pepper), white bread, plain steamed white rice, eggs, and clear chicken or beef broth without any vegetable pieces.

SIBO Treatment Plans

There are a few options to treat SIBO and it will depend on the SIBO test results. We prefer the SIBO herbal treatment instead of antibiotics for SIBO as they have a better safety profile. Your results and approach should be discussed with your practitioners along with any other results.


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How we can help?

If you are experiencing any symptoms with digestive issues or you have symptoms of fatigue, mental health issues or unexplained symptoms, reach out to us at the London Centre for Functional Medicine and we would be happy to schedule a 15 minute free discovery call to talk about options in relation to your health challenges.

What our clients are saying.

Why Choose the London Centre for Functional Medicine?


Once you reach out to us, the team will guide you through the collaborative process with a practitioner, We will gather the information we need to understand you better and help support and motivate you along your health journey.


We take the complex and try to make it simple. Many patients have gone to multiple doctors before they reach us. By taking a functional medicine approach, we can focus on the core imbalance and what needs to be addressed to improve your health picture.

Custom Approach

There is no one size fits approach as each patient is unique. Thus, no plan or protocol is the same. Everything about you including symptoms, lifestyle, diet, genetics and capacity to heal is different and will require a personalized approach.

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