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A Capsule to Look Inside an Irritable Bowel

The ingestible gas sensor

The ingestible gas sensor can give information about the most suitable diet and environmental conditions for each person. Eventually it will provide an image as to how medicine, diet and environment can affect the gut.

By Kourosh Kalantar-Zadeh

The impact of diet and illness on the gut can finally be revealed by swallowing an ingenious capsule that directly measures intestinal gases.

The full text of this article can be purchased from Informit.

Our gut houses a large number of micro­organisms that colonise various part of the gut. The food we ingest activates these bacteria in different locations in the gut.

Complex carbohydrates fermented by these bacteria produce short chain fatty acids that we use as a source of energy. Some of the main by-products of this process are certain gases and vapours of volatile organic compounds.

The main fermentation gas is carbon dioxide. Hydrogen-producing bacteria in both the small and large intestines generate hydrogen (H2), while methanogens found mainly in the large intestine produce methane (CH4). Other gases produced include sulfur-containing compounds like hydrogen sulfide (H2S), which smells like rotten eggs, methanethiol, which smells like rotten fruit, and dimethyl sulfide, which smells like rotting cabbage, as well as nitrogen oxides (NOx) and diverse volatile organic compounds.

While we’re acutely aware that an abnormal increase in the production of intestinal gases causes bloating and flatulence, their impacts are more significant. Gases and volatile vapours of the gastrointestinal tract are directly associated with the state of health and can be used as biomarkers for medical diagnostics. For example:

  • an increase in H2 has been associated with bacterial overgrowth in the small intestine;
  • excessive CH4 in the colon...

The full text of this article can be purchased from Informit.