While bacterium naturally exists throughout the digestive tract, with the highest concentrations of bacteria in the colon, a healthy individual should have relatively low levels of bacteria present in the small intestine. SIBO is the accumulation of an excessive amount of gut bacteria in the small intestine (at least 100,000 bacteria per ml of fluid). However, new guidelines outlining the distinction between each classification have led to the reclassification of methane-related SIBO as Intestinal Methanogen Overgrowth (IMO), since methane in the gastrointestinal tract is produced by archaea, which is not bacteria. SIBO has historically been diagnosed via a hydrogen and methane breath test and either classified as hydrogen-related SIBO or methane-related SIBO. When a patient has SIBO, the digestive system may produce excessive hydrogen and/or methane gas, which can cause many gastrointestinal symptoms such as bloating, diarrhea, cramping, and/or constipation. SIBO is diagnosed when there is an excessive amount of bacteria within the small intestine. In a healthy digestive system, the amount of gut bacteria found within the small intestine is quite low.
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SIBO is an acronym for small intestinal bacterial overgrowth. What is Small Intestinal Bacterial Overgrowth?