SIBO is an acronym for small intestinal bacterial overgrowth. In a normal small intestine, a few strains of bacteria are present. In a small intestine affected by SIBO, abnormal amounts of bacteria are present. Sometimes described as “irritable bowel syndrome (IBS) on steroids,” SIBO often presents with symptoms similar to IBS but more severe. Symptoms of both SIBO and IBS include nausea, bloating, vomiting, diarrhea, constipation, and other signs of gastrointestinal discomfort.
Although SIBO is a recognized condition, it is not a diagnosis because it can be caused by a number of other conditions. Common conditions that have been linked to SIBO include aging, chronic pancreatitis, diabetes, structural defects, injuries, fistulas, and other disorders and diseases of the small intestine. Low stomach acid due to use of medications like those used for gastroesophageal reflux disease, can contribute to SIBO because stomach acid helps destroy ingested bacteria before food moves into the small intestine.
More studies are needed, but many of the suspected underlying conditions include other digestive issues, such as IBS, Crohn’s disease, and celiac disease. In fact, around two thirds of the people who eat a gluten-free diet to manage celiac disease are at increased risk to develop SIBO.
Determining the root cause of SIBO helps determine which treatment strategy to use. Working with both a registered dietitian and a gastroenterologist is the most effective way to diagnose and treat this disorder. Elimination diets are one of the methods a dietitian can help with, finding and eliminating trigger foods and then safely reintroducing foods to the diet as the SIBO resolves.
Because SIBO is the result of another problem, such as a thyroid disorder or other gastrointestinal problem, it is best to identify and treat the underlying condition. As a result, SIBO can be better treated as well. Creating an eating plan, such as a low-FODMAP* diet or low-carb diet, helps keep microbes balanced. Microbes feed on undigested carbohydrates, so identifying which ones are improperly digested can reduce the chance of recurrence. Nutritional deficiencies are common with SIBO, so it is also important to add necessary supplements to the diet to ensure that nutritional needs are met.
* Fermentable, Oligo-, Di-, Mono-saccharides And Polyols