Silhouette of a woman from neck to hips, torso, with chaotic overlapping confusing lines and a question mark encircling her abdomen showing bloating

What Are The Symptoms of SIBO?

That endo belly? What if I told you it might not be all down to endometriosis alone?

Recently, I shared my small intestine bacterial overgrowth diagnosis and my opinion that who present with IBS symptoms for SIBO. Head over to that column to read more and understand why I make this argument, but today, I really want to dive into what SIBO actually is and how it may manifest in terms of symptoms.

What causes SIBO?

As I explained in my previous column, having bacteria in our large intestine is normal and healthy (providing it’s in the right numbers). The small intestine, in contrast, is supposed to have a very minimal amount of bacteria and is the part of the gut where the majority of nutrients are absorbed. SIBO occurs when there’s an overgrowth or accumulation of those healthy bacteria that should be in the large intestine, in the small intestine.

Bacteria eat carbohydrates, which are in the majority of our foods - fruits, vegetables, nuts, seeds, grains, etc. When bacteria eat, they create fermentation, which is essentially the gases they release as a result of consuming carbohydrates. These gases then have an impact on our digestion and our body as a whole, causing multiple health and GI complications.

What are the types of SIBO?

There are three types of SIBO:

  • Hydrogen
  • Methane
  • Hydrogen sulfide

The names are indicative of the kind of gas released by the bacteria.

In the case of methane, it’s actually no longer regarded as classic SIBO but something called intestinal methanogen overgrowth. This is because instead of bacteria being the culprit, methanogens are actually another kind of microorganism called archaea and so slightly different treatment is required. The standard SIBO protocol of antibiotics, antimicrobials or the elemental diet is the same, but methane is much harder to treat and requires different types of antibiotics and antimicrobial herbs in contrast to hydrogen, and this is due to the difference between bacteria and archaea. Intestinal methanogen overgrowth can also occur in the large intestine rather than just the small intestine.

Hydrogen sulfide is another complicated type of SIBO that is harder to detect as there’s not yet a test for it (though one is in development) and again, it’s harder to treat.

What are the symptoms?

Some of the classic signs of SIBO include:

  • A visibly boated stomach or the feeling of being bloated
  • Constipation (normally associated with methane type SIBO)
  • Diarrhea (normally associated with hydrogen type SIBO)
  • Fatigue
  • Burping
  • Acid reflux
  • Nausea
  • Flatulence
  • Anxiety and/or depression
  • Abdominal pain
  • Brain fog
  • Food reactions that tend to worsen over time
  • Unexplained weight loss or weight gain (weight loss is generally associated with hydrogen and weight gain with methane)

Is SIBO dangerous?

There are also specific nutrient deficiencies associated with SIBO:

  • Low ferritin
  • Low B12
  • Vitamins A, D, E, K deficiencies
  • Low omega 3 fatty acids
  • Low protein

These occur because of the multitude of problems the SIBO causes with our ability to absorb food. Firstly, the SIBO eats our food so our body is constantly missing out on valuable nutrients. Additionally, it also reduces our stomach acid and digestive enzymes, making it much harder for us to break down and digest food. Finally, SIBO negatively affects the bile, making fat absorption much harder and minimizing the ability to absorb fat-soluble vitamins.

Finally, hydrogen sulfide can also cause another collection of symptoms in addition to the above:

  • Bladder pain
  • Bladder frequency and/or urgency
  • Tingling or numbness in hands, arms, feet and legs
  • Body pain (generally muscular)
  • Sulfur smelling gas (though this is generally less common)
  • Symptoms triggered after sulfur containing foods or an Epsom salt bath
  • Worse food intolerances and sensitivities i.e. histamines

Your SIBO symptoms may differ depending on the type of SIBO you have and you don’t need to have all the symptoms to have SIBO, so if you suspect it, it’s worth being tested.

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This article represents the opinions, thoughts, and experiences of the author; none of this content has been paid for by any advertiser. The team does not recommend or endorse any products or treatments discussed herein. Learn more about how we maintain editorial integrity here.

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