You have probably heard the term SIBO before. Maybe from your doctor or a friend or even in an article online. SIBO is something we could call a trendy diagnosis as it has become a popular diagnosis in recent years. Today I'd like to share some more info and dispel some common misconceptions about SIBO—and no, probiotics do not “cure” SIBO, despite what the internet might tell us!
SIBO stands for ‘small intestinal bacterial overgrowth’ and is the presence of excessive bacteria in the small intestine. The small intestine is where most of the nutrients from our food are absorbed and there shouldn't be too many bacteria living in the small intestine (compared to the bacteria-rich colon). However, it can become hospitable to bacteria and lead to bacteria growing excessively.
Many people believe that SIBO is an infection, similar to a getting the “stomach bug.” However, SIBO is actual a symptom of a different health issue. In fact, there are many different potential causes for SIBO, such as—chronic uses of acid suppressing medications (PPI), undiagnosed or poorly controlled celiac disease, extensive prior antibiotic exposure, abnormally slow motility, low levels of stomach acid due to old age or an autoimmune disease, prior intestinal surgeries for weight loss, having an outpouching or diverticulum in your small intestine, Crohn’s disease, chronic alcohol use and pancreatic insufficiency.
Symptoms of SIBO will present the same, no matter what the underlying cause is. The most common symptoms experienced with SIBO are bloating, abdominal distention, diarrhea, abdominal pain and fatigue. Bloating with SIBO is usually very consistent, even with foods that have never caused bloating for you before. Another symptom that may be the most uncomfortable, or maybe more so for others around you is the gas associated with SIBO.
When folks with SIBO eat a meal, the nutrients they consume can quickly be shared with the overgrowth of bacteria in the small intestine. These bacteria ferment certain nutrients and gas is just a by-product of this process. This is what contributes to the extremely uncomfortable bloating associated with SIBO. In severe cases of SIBO, bile acid malabsorption can occur, which is when the body’s bile-recycling system is interfered with and permits excess bile. This can result in diarrhea and vitamin deficiencies.
The most common way to diagnose SIBO is through breath testing. This test entails drinking a sugar solution and breathing into a bag periodically over three hours and having your breath gasses measured by a machine. The test will measure hydrogen and methane, two types of gas. Only bacterial cells will produce these gasses when they encounter the sugar that was consumed.
Another misconception about SIBO is that it is treated with diet. This is actually not the case. SIBO symptoms can most likely be managed by diet, but SIBO must be treated with prescription antibiotics. One of the most common antibiotics used is Xifaxan, although your doctor should determine which antibiotic is best for you, as antibiotics target different types of organisms that can cause overgrowth.
Many people attempt diets to get rid of SIBO, but unfortunately the scientific research does not currently support an evidence-based diet approach for this purpose. Rather than attempting different diets (which can get restrictive and cumbersome) it’s important to work with your medical team to treat the underlying cause of SIBO. If the underlying cause is not corrected, there is a chance that you may develop SIBO again even after antibiotic treatment.
Dukowicz, Andrew C et al. “Small intestinal bacterial overgrowth: a comprehensive review.” Gastroenterology & hepatology vol. 3,2 (2007): 112-22.
