Our microbiome is the collection of microbes, in and on our bodies, that offer us a mutual benefit.
The health of our microbiome dictates our overall health status. Human cells outnumbered by the number and variety of microbes in our bodies. Our microbiota, the friendly microbes in our gut, help to digest food, strengthen our immune system, defend our intestines from unfriendly bacteria, and heal our gut (1). The balance of our gut microbiota lies in a complex relationship between our genetics, diet, environment, and even our social circles.
When poor stomach acid secretion fails to defend against colonies of foreign microbes, an overgrowth of these bacteria in the small intestine leads to an imbalanced microbiota. Also, digestive tract abnormalities, abdominal surgery complications, and impaired gallbladder & pancreatic function can allow overgrowth of foreign microbes that disturb the balance of our gut bacteria.
Impaired migrating motor complexes (MMC) also set the stage for foreign bacteria to colonize the small intestine (2). MMC initiates peristalsis, the muscular contraction of our intestines that moves food through the gut into the colon. MMC also occurs in a fasting state and acts to sweep unfriendly bacteria into the colon, limiting SIBO (3).
The vagus nerve controls MMC during parasympathetic nervous system activity (our rest and digest functions). The strength and conditioning of the vagus nerve (‘vagal tone') also dictate our heart rate and breathing rate. The vagal tone will be improved by practicing yoga (4). Interestingly, deep laughter also stimulates the vagus nerve (5). Like to sing in the shower? Singing and making music also enhances the vagal tone (6).
What about SIBO and its relation to IBS?
People suffering from IBS and SIBO require digestive support coupled with the eradication of bacterial overgrowth (7). SIBO symptoms overlap with the gas, bloating, diarrhea, constipation, and abdominal pain that is common in IBS.
More than half of all IBS patients have SIBO, and about half of all celiac cases also have SIBO (8). In celiac disease and SIBO, intestinal inflammation causes problems with nutrient absorption in the small intestine.
As a result, patients are typically deficient in iron and vitamin B12; nutrients that are absorbed in a healthy small intestine. A lack of MMC also affects the secretion of bile for the digestion and absorption of fats and fat-soluble vitamins A, vitamins D, vitamins E, vitamins K in the small intestine (9). In SIBO, some bacteria also digest bile before we can use it, further contributing to fat and fat-soluble vitamins ending up in the stool (2). Weight loss due to malnutrition is a common symptom in long-standing celiac disease and SIBO.
How is SIBO diagnosed?
Since bacteria can squander bile acids needed for digestion and absorption of fats, the initial breath test for SIBO was the bile acid breath test. Bile acid breath testing fell out of favour, and now hydrogen and methane breath tests are used in the diagnosis of SIBO (7).
Patients are instructed to fast, then consume a lactulose or glucose drink. If SIBO is present, bacteria in the small intestine will begin to digest the sugars into hydrogen and methane before the normal colonic bacteria do the same.
The reliability of breath testing for SIBO has been brought into question due to the variability in normal and abnormal results (9).
so what can you eat to cut down on methane and hydrogen-producing bacteria?
In terms of dietary recommendations for SIBO, there is no one size fits all approach. The FODMAPs diet, Specific Carbohydrate Diet (SCD), or Gut and Psychology Syndrome diet (GAPS) may work for some patients, but not others. Identifying your food triggers is essential.
Once bacteria levels and SIBO symptoms have been reduced, patients enter a recovery phase to rest and replenish the gut. Certain strains of probiotics can alleviate SIBO after short term therapy, and it is vital to speak with your doctor about which probiotics are most appropriate for you (12).
what are some ways to help manage sibo in my day today?
Successful treatment of SIBO, as with any chronic disease, relies on a holistic focus. Equal emphasis must be put on eradicating bacteria, repopulating with probiotics, restoring vagal tone/MMC, avoiding food triggers, and healing the gut. Above all, you should know that the road to recovery will never be linear; relapses are inevitable (13).
Understanding mental-emotional health as an overarching goal will help give a big-picture context and build defences against stress. Awareness of the connection between our mind and body is what will lead to building back digestive defences. Finding enjoyment in exercise will also lead to improvements in MMC (14). Seeing something that brings you joy, something that leads you to more self-expression, is what will lead to a significant change. Rest and Digest!
For more information on SIBO: www.sibocenter.com
- Gerritsen J., Smidt H., Rijkers GT., de Vos WM. Intestinal microbiota in human health and disease: the impact of probiotics. Genes Nutr 6; (2011): 209-240. Print.
- Miyano Y, et al. The role of the vagus nerve in the migrating motor complex and ghrelin-and motilin-induced gastric contraction in suncus. PloS one 8.5 (2013). Web.
- Deloose E., Janssen P., Depoortere I., Tack J. The Migrating Motor Complex: Control Mechanisms and Its Role in Health and Disease. Nature Reviews Gastroenterology & Hepatology 9.5 (2012): 271-85. Web
- Streeter C., et al. Effects of yoga versus walking on mood, anxiety, and brain GABA levels: a randomized controlled MRS study. The Journal of Alternative and Complementary Medicine 16.11 (2010): 1145-152. Web.
- Miller M., Fry WF. The effect of mirthful laughter on the human cardiovascular system. Medical Hypotheses 73.5 (2009): 636-39. Web.
- Vickhoff B, Malmgren H, Astrom R, Nyberg G, Ekstrom S-R, Engwall M, et al. Music structure determines heart rate variability of singers. Frontiers in Psychology Auditory Cognitive Neuroscience 334.4 (2013): 1-16. Web.
- Ghoshal, UC., et al. A proof-of-concept study showing antibiotics to be more effective in irritable bowel syndrome with than without small-intestinal bacterial overgrowth: a randomized, double-blind, placebo-controlled trial. European journal of gastroenterology & hepatology (2016).
- O'Leary, C. Small bowel bacterial overgrowth, celiac disease, and IBS: what are the real associations?" The American Journal of Gastroenterology 98.4 (2003): 720-22. Web.
- Simren M, Stotzer P-O. Use and abuse of hydrogen breath tests. Gut 55.3 (2006): 297-303. Web.
- Ghoshal, Uday C. Overview of Hydrogen Breath Tests in Gastroenterology Practice. Evaluation of Gastrointestinal Motility and Its Disorders (2016): 87-94. Web.
- Chedid, Victor, et al. Herbal therapy is equivalent to rifaximin for the treatment of small intestinal bacterial overgrowth. Global Advances in Health and Medicine 3.3 (2014): 16-24.
- Kwak DS, Jun DW, Seo JG, Chung WS, Park SE, Lee KN, et al. Short-term probiotic therapy alleviates small intestinal bacterial overgrowth but does not improve intestinal permeability in chronic liver disease. Eur J Gastroenterol Hepatol 26.12 (2014): 1353-1359. Web.
- Grover, Madhusudan, et al. Small intestinal bacterial overgrowth in irritable bowel syndrome: association with colon motility, bowel symptoms, and psychological distress. Neurogastroenterology & Motility 20.9 (2008): 998-1008.
- Soffer EE, Sumers RW, Gisolfi C. Effect of exercise on intestinal motility and transit in trained athletes. Am J Physio 5.1 (1991): 698-702. Web.