SIBO, What You Can Do About It

Photo credit: Michael Schiffer

Photo credit: Michael Schiffer

SIBO is short for small intestinal bacterial overgrowth. You are supposed to have lots of bacteria in your large intestine (colon). In fact, this is where your gut microbiome actually is found.

Sometimes this bacteria ends up in your small intestine in abnormally large amounts, and it certainly doesn't belong there.


There are 3 types of SIBO you may have heard of. Hydrogen, methane, and hydrogen sulfide SIBO. The 2 better known types are hydrogen dominant and methane dominant SIBO. 

In your gut, bacteria produce hydrogen (as a byproduct of carbohydrate fermentation) and archaea produce methane. Hydrogen SIBO tends to cause diarrhea, and methane constipation. Archaea feed on hydrogen and make methane as a byproduct, and this can reduce levels of hydrogen. This is why sometimes hydrogen breath tests are negative when SIBO is actually present.

Hydrogen sulfide is important for a variety of biochemical functions in the body, however its overgrowth can cause SIBO, and it tends to affect your upper gut. Most with this issue also have methane dominant archaea overgrowth in the small intestine, and constipation is more common. Hydrogen sulfide SIBO doesn’t show up on typical breath tests.

Since testing doesn’t always give us an accurate picture, if you have symptoms of SIBO (IBS symptoms like gas, bloating, belching, constipation and/or diarrhea) and a negative breath test, using interventions for SIBO can be helpful. Hydrogen sulfide SIBO can also cause rotten egg like breath, flatulence and stools.


It is through the lining of your small intestine where many of your nutrients are absorbed so that your body can use them for fuel. When you have abnormally large amounts of bacteria in your small intestine as can occur with SIBO, you become unable to digest and absorb nutrients from the foods you eat.  This means that having SIBO can lead to nutrient deficiency, even if you are eating a nutritious diet.


Because the bacteria that cause SIBO ferment carbohydrates in your gut, starchy and sugary foods can feed the overgrowth. If you have strong carbohydrate and/or sugar cravings it can be due to gut infections like SIBO. The bacteria are hungry and are encouraging you to feed them. The gases produced in this process result in symptoms like gas, bloating, belching, constipation, and/or diarrhea.


When you have SIBO, finding the root cause is important. There are a variety of issues that can lead to SIBO:

  • Poor diet

  • Inappropriate diet (that might seem healthy, some fad diets can fall into this category)

  • Stress

  • Low gut motility (common with low thyroid/hypothyroid)

  • Lack of digestive factors

SIBO is hard to eradicate because we neglect to address why it happened in the first place, and take into account potential underlying factors like these (this is by no means an exhaustive list).

You can treat SIBO with antibiotics, natural antimicrobials and diet until the cows come home, but unless you address the underlying cause, it’s like sprinkling drops of water on a raging fire, you’ll never get that fire out.


As the problem continues, inflammation in your gut causes the normally tight junctions holding the cells of your gut lining together to loosen. This results in leaky gut, allowing particles of food and toxins from bacteria to enter your bloodstream. Your immune system mounts a response, and over time this can lead to autoimmune disease.  SIBO also can be linked to skin conditions like eczema and other skin rashes because of this issue.

Probiotics and SIBO are a controversial topic. Remember that SIBO is an overgrowth of bacteria. Adding more bacteria, as is the case when you take a probiotic isn’t necessarily a good idea. Determining if using a probiotic (and which one) is right for you should be done with professional guidance.

SIBO often isn’t the only gut imbalance/infection occurring so a comprehensive assessment of your gut health and gut microbiome can help guide interventions. You may need to address more than SIBO.


SIBO is stubborn. Many suffer for years. In order to resolve the problem you must address the underlying cause of it. This is often missed, which is why you can't get rid of your SIBO.


Protocols that are successful in eradicating SIBO take into account multiple interventions, and addressing the underlying cause.


Everyone is different. There is no one size fits all approach. Your plan will be unlike anyone else's. 

Working with a professional who can connect the dots between your unique needs and best practices in SIBO eradication is essential if you want freedom from it once and for all.