Hydrogen/methane breath testing is a diagnostic method that can let you know of potential problems that you have with digesting and absorbing foods. But what exactly is it and how does it work? Read on for more.
What is Hydrogen/Methane Breath Testing?
Hydrogen/methane breath testing is used to determine if a person has a sensitivity to or trouble absorbing a certain type of sugar such as fructose, lactose, or glucose. This is done by measuring the levels of hydrogen and or methane in your exhaled breath. The idea is that if a person has trouble absorbing a sugar, the bacteria breaking down the sugar in the large bowel will produce hydrogen and or methane. This occurs if the sugar is not absorbed through the gut wall in the small bowel.
A hydrogen/methane unit is more sensitive and more stable than a hydrogen only unit, making it a better choice for breath testing.
Uses for Hydrogen/Methane Breath Testing
Hydrogen/methane breath testing can determine if a person has trouble absorbing a specific type of sugar. For example, if a person cannot fully absorb fructose, they may experience symptoms such as diarrhea, constipation, bloating, stomach noises, flatulence, lethargy, or headaches. If a person cannot fully absorb lactose (is lactose intolerant), they may suffer from similar symptoms as described for fructose. A glucose test is performed to determine if a person is suffering from small bowel bacterial overgrowth. The symptoms of such may be similar to those of fructose or lactose malabsorption but different treatment is required.
The Hydrogen/Methane Breath Testing Process
Before the test can be performed, it is important that the person follows a very specific diet for a full day before the test. The purpose of the diet is to reduce the level of bacterial activity in the gut. When the test is carried out, the first thing done is to create a "baseline" sample using the lactulose control test. Once the baseline sample has been created, the person drinks a sugar drink. Their breath is then tested every 20 minutes for at least two hours. A longer test period may be required, but is not longer than three hours. If a sugar is not being absorbed correctly, bacteria in the gut will break down the sugar, causing higher hydrogen and/or methane readings to show up in the breath tests. The differences between the control test and the subsequent tests help to determine if sugar absorption is a problem.
It should be noted that the tests for lactulose, fructose, lactose, and glucose should be performed on separate days, with at least one day's rest between each type of test.
Contraindications for Hydrogen/Methane Breath Testing
You cannot undergo hydrogen breath testing if you have had a colonoscopy, barium enema, or any other test that requires bowel prep, as the bowel prep will cleanse the bacteria. If you have had one of these tests, you will need to wait at least four weeks in order to allow the bacteria to re-establish themselves in the colon. Do not smoke the day before or on the day of the test as it can affect the result. On the day of the test, don't chew gum or use mouthwash and use only a small amount of water to brush your teeth. Don't eat or drink anything, including water for the specified amount of time before the test.
Originally published on Mar 15, 2009
