What is SIBO? The bacterial overgrowth may impact millions of Americans
If you often battle uncomfortable gastrointestinal symptoms, you’re not alone. A survey of over 71,000 Americans found that 2/3 of individuals reported symptoms of gastrointestinal distress.
Though an occasional case of bloating, stomach pain or gas may not mean much, when these symptoms become more prevalent, it could be a sign of a more significant medical issue.
Small intestinal bacterial overgrowth (SIBO) is a condition that accompanies many gastrointestinal disorders. When something is off in the gut it can cause an imbalance of bacteria in the small intestine and this is when SIBO can occur.
What is SIBO?
Though some bacteria are expected in the small intestine, a large amount are not and can interfere with normal functioning. SIBO is defined by the American Journal of Gastroenterology as “the presence of excessive numbers of bacteria in the small bowel, causing gastrointestinal symptoms” and is thought to impact millions of Americans.
Studies show the condition often goes undiagnosed, and milder cases may present no symptoms at all. Kendra Weekley is a registered dietitian in the Department of Human Nutrition at the Cleveland Clinic. She counsels patients with SIBO and says that the condition often results from something else in the GI tract, so if the primary problem is not resolved, SIBO can reoccur.
Risk factors and causes of SIBO
Overgrowth of small intestinal bacteria can occur anytime the flora of our microbiome is negatively impacted. Studies show that SIBO may be a common manifestation of specific GI disorders, such as IBS (irritable bowel syndrome) or Crohn’s disease.
Still, many other conditions may put an individual at risk as well. These include:
Motility disorders
Inflammatory Bowel Disease (IBD)
Bile duct problems
Liver disease
Advanced age
Abdominal surgery disorders
Being on medications that disrupt low stomach acid
SIBO symptoms
Symptoms of SIBO are broad in both scope and severity. Though symptoms of SIBO vary in each patient, common symptoms include chronic diarrhea, weight loss, stomach pain and malabsorption. Weekley tells TODAY.com that symptoms can be broad and include “nausea, bloating, flatulence, abdominal distension, abdominal cramping, abdominal pain, diarrhea and/or constipation.”
Dr. Ibrahim Hanouneh, gastroenterologist and hepatologist with MNGI Digestive Health in Minneapolis, MN, sees many patients in his practice with SIBO and says that he considers it quite common in patients with Type 2 diabetes and among those with prior abdominal surgeries. He adds that his patients who have SIBO typically present with abdominal bloating, distention, gas and altered bowel habits.
How to diagnose SIBO: SIBO tests
Diagnosing SIBO can be challenging. Studies indicate a need for more consensus on the best way to diagnose the condition. However, breath and bacterial culture tests are two common approaches with varying degrees of risk and accuracy.
A breath test is a non-invasive approach and the more commonly used testing mechanism. These tests assess the presence of gases (hydrogen and methane) expelled during the incomplete breakdown of sugars. Studies show that the type and accuracy of breath tests may vary, and false negatives and positives can occur.
Bacterial culture tests assess the specific bacteria in the small intestine and are done via an upper endoscopy. They are considered the gold standard, according to the Mayo Clinic, however, the test is invasive, making it riskier than a breath test, and it can be costly.
SIBO treatment
The first step in treating SIBO is to identify the medical problem causing it. Antibiotics are a common treatment, as they can help reduce abnormal bacteria in the small intestine. Hanouneh tells TODAY.com that in his practice, patients usually see a significant improvement after a course of antibiotics.
Nutritional intervention to address deficiencies and symptoms can also be prescribed. This may include supplementation of vitamins and minerals that may be missing or dietary interventions such as a low-FODMAP diet or the elemental diet.
Diets to Consider with SIBO
The low FODMAP diet
The low FODMAP diet is effective in IBS patients in terms of improving GI-related symptoms. The diet reduces or eliminates foods that are hard to digest and are high in gas-producing carbohydrates. FODMAP stands for:
Fermentable
Oligosaccharides
Disaccharides
Monosaccharides
Polyols
A low-FODMAP diet typically contains multiple phases and is not a good fit for everyone. Additionally, more research is needed on the effectiveness of the diet alongside antibiotic treatment.
The elemental diet
In some cases where patients have tried diet and antibiotic therapy and they have failed, there have been some small studies on using a short-term elemental diet, says Weekley. This diet lasts 14 days and consists of replacing all food and drink with a liquid meal replacement formula to meet estimated calorie and protein needs; typically, no other food is ingested. These diets are challenging as many of these products are not palatable and can be expensive.
Other dietary considerations for SIBO found in the research include a vegetarian or vegan diet and even the inclusion of probiotics. However, it needs to be clarified if probiotics improve or make SIBO worse, so more research is required.
Foods to avoid on the SIBO diet
Working with your healthcare provider on implanting a FODMAP dietary pattern may be a step toward alleviation of symptoms, especially if you have already been diagnosed with IBS. Since the diet is meant to reduce difficult-to-digest (and gas-producing foods) you should focus on limiting or avoiding:
Products containing cows milk, such as ice cream and yogurt
Beans and lentils
Wheat based foods such as bread, pasta and crackers
Foods in the allium family, such as garlic, shallots and onions
Stone fruits, such as nectarines, cherries and peaches as well as other fruits such as apples
Vegetables such as artichokes, asparagus and cruciferous vegetables such as cauliflower
Processed meats
Honey, high fructose corn syrup and sweeteners containing sugar alcohols (often found in sugar free candy and gum)
Foods to eat on the SIBO diet
You may focus on consuming these low-FODMAP foods instead:
Protein sources such as fish, chicken, eggs and beef
Healthy fats like extra virgin olive oil
Gluten-free grains such as rice and corn
Lactose free dairy products
Berries, bananas and strawberries, oranges, lemons, limes, grapes and strawberries
The bottom line
Working with a physician and dietitian to monitor dietary interventions is critical since there is no “one size fits all” approach to SIBO. Some diets may be highly effective in treating symptoms, while others may worsen symptoms. The key is to determine the underlying cause of SIBO and then work with your medical team on a treatment that meets your needs.
This article was originally published on TODAY.com
