What is SIBO? Is it connected to IBS or Gluten?

What Is SIBO? Are SIBO Symptoms Related To IBS Or Gluten?

By Amy Burkhart, MD RD

What Is SIBO?  What are the symptoms of SIBO? Is there a SIBO test? What about a SIBO diet?  Are SIBO, Gluten, and IBS intertwined? And most importantly, what can you do to feel better?

SIBO stands for small intestinal bacterial overgrowth. Normally, the small intestine has few bacteria. Most intestinal bacteria are contained in the large intestine. When there are too many bacteria in the small intestine, it is called SIBO.

• Bloating- Most common symptom
• Gas
• Stomach pain
• Diarrhea
• Weight loss
• Fatigue
• Nausea
• Nutrient deficiencies and their associated symptoms: Vitamin B12, A, D, E, iron, other B vitamins, fat, protein and carbohydrate malabsorption
• Carbohydrate intolerance-symptoms such as bloating/pain/gas fatigue after eating
• Constipation
• Joint pain
• Depression
• Anxiety

To keep bacteria counts at a healthy low level in the small intestine, your body must have:

• Normal levels of stomach acid
• A properly functioning pancreas and gall bladder
• Normal intestinal motility (ability to move food through the digestive tract)
• Normal mucosa (lining of the digestive tract)
• Normal valves in the intestine-think of these as “doors’ in the intestine that open and close. If the doors are broken, things can go wrong.

The following medical conditions and treatments can increase the risk of developing SIBO.

• Diabetes
• Liver or pancreas disease
• Celiac Disease/Non-celiac Gluten Sensitivity
• Inflammatory Bowel Disease
• Hypothyroidism
• IBS
• Chronic Constipation
• Chemotherapy
• Frequent Antibiotic Use
• Immune suppressed states, i.e., AIDS, Cancer, chronic steroid use.
• Other chronic diseases
• Chronic use of acid-blocking medication

In addition to the conditions listed above, SIBO is more common in people with rosacea, restless leg syndrome, interstitial cystitis, and cirrhosis.

The best test for SIBO is a hydrogen breath test. A person drinks a sugar-containing drink, and exhaled gases are measured. If there are too many bacteria, excess gases (hydrogen, methane, or both) will be produced. It should be noted that the reliability of this test is less than ideal. Due to the poor reliability of the testing method, some physicians will treat based on symptoms. A direct sample can also be taken from the intestinal fluid to diagnose SIBO, but it is not routinely done.

Watch a video of a breath test here

People with celiac disease have an increased risk of SIBO. A research paper found a higher incidence of SIBO in celiac patients ( already on a gluten-free diet ) with ongoing symptoms.

There appears to be a higher incidence of SIBO in non-celiac gluten sensitivity (NCGS) patients, but no studies are connecting the two yet. The science is that the arena is rapidly evolving.

Most cases of gluten sensitivity are due to FODMAP intolerance; The low FODMAP diet helps IBS. IBS is connected to SIBO. Hence the connection is emerging, just not yet in a research paper.

Irritable bowel syndrome (IBS) is a common condition. A person with IBS typically has symptoms such as bloating, cramping, abdominal pain, diarrhea, and/ or constipation.

There is no definitive test for IBS, so diagnosis is based on symptoms and history. Until we have a better understanding of IBS, there will be a debate on its cause and treatment.

Some studies say that up to 50-60% of people with IBS may have SIBO and that by treating the SIBO, IBS symptoms resolve.

So, are some cases of IBS actually SIBO?  A  review paper addressed the use of Rifaxamin, an antibiotic used to treat SIBO as a treatment for IBS patients.  Many studies showed improvement or resolution of IBS symptoms if the IBS patients were diagnosed with SIBO.

Another study in children found that 66% of children diagnosed with IBS had SIBO. Treating the SIBO resolved the IBS symptoms.

The underlying cause of the SIBO must be addressed first or treatment will not be effective. For example, if SIBO is due to celiac disease it will never get better without first adhering to a strict gluten-free diet. After treating the underlying cause, the subsequent therapy will depend on a traditional or integrative approach.

Antibiotics are the mainstay of therapy and are often used in conjunction with motility agents to prevent the “build-up” of bacteria by moving things through the intestinal tract.

Some physicians will also prescribe a low sugar diet. In severe cases, elemental diets are used. These are liquid diets in which all of the nutrients are broken down and don’t require digestion. The nutrients are absorbed so quickly that the bacteria don’t have time to act on them and produce symptoms. This is done for a short duration to effectively “starve” the bacteria.

As mentioned above, the underlying cause must first be treated. From there, the following integrative therapies may be used:

• Probiotics +/-
• Vitamins
• Diet/nutritional interventions
• Motility agents
• Digestive Enzymes
• Acupuncture
• Elimination Diets
• Hypnotherapy
• Relaxation Techniques
• Stress Reduction
• Addressing sleep disorders
• Herbal antibiotics
• Elemental Diets
• Antibiotics

Many diets are used to treat SIBO. Which diet is used depends on the clinical scenario and the practitioner.

Most of the diets have the same goal of reducing sugars that the bacteria would consume.

• A general low sugar/carb diet is preferred if symptoms can be controlled.
• Other diets used are:
• Low FODMAP
• SCD- Specific Carbohydrate Diet
• GAPS- Gut and Psychology Syndrome Diet
• Candida diet
• Paleo-The Paleolithic Diet
• Ketogenic diet
• A ” SIBO Diet” is often a combination of the low FODMAP diet and the SCD diet, but this strict of a dietary regiment is not always needed. A handout of the diet can be found here.
• Cedars Sinai low fermentation diet

• Long term outcome varies, but recurrence is common.
•  Prevent recurrence: You may be able to prevent or minimize the risk of recurrence by eating a “clean diet” of primarily plant-based whole foods; minimizing processed foods and sugar; reducing stress; exercising; and adopting good sleep habits. Some people will use a less restricted form of one of the above-mentioned diets on a long term basis; each person is different.

She came into my office complaining of bloating and was convinced it was from something she was eating. In a way, she was right. Bloating can be caused by many things, some minor, some serious. It was severely impacting her day-to-day life and her overall health. Because of the discomfort from the severe bloating, she was unable to sleep. In turn, the sleep deprivation was markedly impacting her mental and physical health. Prior to our visit, Clare had tested negative for celiac disease but had started a gluten-free diet to help her rheumatoid arthritis and bloating. Her symptoms were not resolving. Her doctor told her she had IBS, but she wanted to know if there was something she could do to find relief.

The cause of her bloating did turn out to be SIBO. Her intuition was correct; what she was eating was bothering her. The sugar in her diet was an issue, due to SIBO and FODMAP Intolerance We addressed these issues, identified and treated both, and she is on her way to a new level of energy and health.

• If you think you may have symptoms consistent with SIBO, I encourage you to discuss the possibility with your physician.
• Underlying reasons need to be identified to ensure the best outcome
• Dietary changes mentioned above, addressing sleep, stress, and overall wellness can help reduce symptoms while you wait for the evaluation.
• Don’t give up, many practitioners are not familiar with SIBO. Bring them printed research papers to help educate them. There are a few listed below.
• Be proactive- you can feel better!

• Overview of SIBO 2019 –https://pubmed.ncbi.nlm.nih.gov/30645678/
• How to test and treat SIBO: https://pubmed.ncbi.nlm.nih.gov/26780631/
• Testing for SIBO- a consensus paper: https://pubmed.ncbi.nlm.nih.gov/28323273/

THIS ARTICLE IS COPYRIGHTED BY AMY BURKHART, MD, RD.

Dr. Amy Burkhart is a doctor (M.D.), Registered Dietitian, R.D., and fellowship-trained in integrative medicine. She specializes in treating chronic digestive disorders from an integrative/functional medicine perspective.