What Is Methane SIBO and What To Do About It?

Methane small intestinal bacterial growth (SIBO) is described as a distinct form of SIBO due to specific differences, the methane-dominant type is often referred to as intestinal methanogen overgrowth or IMO instead of SIBO [1]. This term reflects the microorganisms involved called methanogens, which belong to a non-bacterial species known as archaea [2]. Another difference is that methanogen overgrowth can extend outside the small intestine into the large intestine. However, this form is still currently called methane SIBO even though it can move outside of the small intestine.

What is SIBO?

SIBO refers to dysbiosis or gut microbiota imbalance due to the overgrowth of harmful invaders in the gastrointestinal (GI) tract. The signs of SIBO include [2, 3]:

  • Acid reflux and belching
  • Abdominal aches and discomfort
  • Bloating and flatulence after meals
  • Chronic constipation, and/or diarrhea
  • Intolerance for high FODMAP foods

FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides, and polyols, which are carbohydrates that rapidly ferment while also being resistant to complete digestion [4].  

There are different types of SIBO, mainly methane SIBO and hydrogen SIBO. Methane SIBO or IMO is usually accompanied by constipation, while hydrogen SIBO may cause diarrhea, or loose stools [3].

Why the Root Cause of Methane SIBO Is Really Hydrogen SIBO

One of the main reasons that Methane SIBO was given this term is due to its association with hydrogen SIBO. When people start to eat, gut bacteria begin to aid digestion through carbohydrate fermentation—a process that leads to the production of hydrogen gas [5, 6]. Hydrogen is a food source of archaea, which are the methanogens that are responsible for gut microbiota imbalance when they rapidly grow in number [2]. However, as methanogens consume the hydrogen, they release their own gas—methane [2, 5].archaea SIBO 

In most cases, this occurs because an individual probably has a simultaneous overgrowth of harmful hydrogen-producing bacteria in the gut or hydrogen SIBO [2, 5, 6]. This means that most people appear to suffer from methane SIBO and hydrogen SIBO at the same time.

Methane and hydrogen gas are detected through breath tests and excess levels of hydrogen that would normally indicate the presence of hydrogen SIBO may not always show up on the test results if large amounts of methanogens are quickly consuming the hydrogen that the harmful bacteria are producing.

Therefore, when either form of SIBO is detected, a similar form of intervention can help combat both issues. A beneficial approach involves supplementation with a combination of probiotics, enzymes, and phage therapy. 



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