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Why Is Measuring Hydrogen Sulfide Important?

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It’s common knowledge that there is gas in your body. While healthy levels of these gases help

contribute to a balanced gut, abnormal levels of gases can indicate certain conditions like small

intestinal bacterial overgrowth (SIBO) and cause frustrating symptoms. There are three primary

gases found in the gut microbiome: hydrogen, methane, and hydrogen sulfide; although

hydrogen sulfide is only recently detectable through the three-gas breath test, trio-smart®.

Patients with elevated hydrogen sulfide often went unrecognized by one-gas or two-gas breath

tests prior to trio-smart’s breakthrough three-gas technology.

Measuring Only Hydrogen and Methane Is Incomplete.

Hydrogen, methane, and hydrogen sulfide interact with each other in a complex and

interesting way. Hydrogen is produced by fermenting bacteria but is also consumed by

other organisms, resulting in the production of other gases, including methane and

hydrogen sulfide. 


There is a balance-counterbalance effect between methane and hydrogen sulfide,

illustrating a biochemical interdependency between microbes in the microbiome. These

findings are important, because they indicate limitations when measuring only one or two of

the three primary fermented gases.

Interplay of Gases
What Is Hydrogen Sulfide?

Hydrogen sulfide is a colorless gas often found in the gut. Hydrogen sulfide is produced

when hydrogen sulfide-producing organisms consume hydrogen and can lead to

uncomfortable GI symptoms, like diarrhea.

What Are the Symptoms of Abnormal Hydrogen Sulfide?

Patients with excess hydrogen sulfide experience symptoms like abdominal pain, bloating,

gas, distension, flatulence, and especially diarrhea. These symptoms are usually

experienced once a week or more for at least four weeks. Excess hydrogen sulfide shares

many of the symptoms of IBS-D (diarrhea-predominant irritable bowel syndrome) and IBS-

M (mixed-diarrhea/constipation irritable bowel syndrome). Abnormal levels of hydrogen

sulfide predict more severe diarrhea, and the level of hydrogen sulfide measured correlates

with the severity of diarrhea. Elevated levels of hydrogen sulfide are indicative of excess

hydrogen sulfide.

How Do You Test for Hydrogen Sulfide?

You can measure levels of hydrogen sulfide with a breath test. While 2-gas legacy breath tests

only measure hydrogen and methane, trio-smart is the only 3-gas breath test available that

measures hydrogen sulfide, as well. Learn more about breath testing with trio-smart here.

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