Improve Your Success Rate in Treating IBS

“(I am unable) to function normally—have severe fatigue, severe GI symptoms and urgency, difficulty being out of house, extremely limited diet; no matter what I do, the symptoms are worsening and regularly flaring. I cannot work and have kids. I have sought medical care over and over with not much help, am often dismissed and not taken seriously.” – Canadian patient living with IBS1

In 2016, the Gastrointestinal Society of Canada published results from a survey of patients diagnosed with irritable bowel syndrome (IBS) in an effort to understand the ways this condition affects daily life; the quote above was just one among many statements made by patients living with this chronic, often debilitating disorder.1 Studies suggest that 53% of patients with IBS have suffered for more than 10 years with symptoms including abdominal pain, bloating, and constipation and/or diarrhea.2

Learn more about Functional Medicine 

The prevalence of IBS is approximately 10% in Western countries, and yet only half of these patients consult a clinician.2 And although each person has a unique IBS experience within the range of known symptoms, studies suggest that this condition may significantly decrease a person’s quality of life.3,4 Symptom severity, in relation to bowel function or abdominal pain, has been shown to have the most important effect on reducing quality of life in IBS patients.2 A US survey of 350 IBS patients found that two-thirds of respondents reported missing an average of over 10 activities or social events over a three-month period due to IBS, equivalent to one activity per week,5 and 20% of IBS-D (IBS with predominant diarrhea) patients agreed with the statement, “My IBS has badly affected my working life.”6

There need to be studies done to help people get their lives back. You should be able to go out and have lunch with family and friends instead of worrying when this will hit you because there is no ‘if’ – it’s ‘when,’” said a patient from the 2016 Canadian Gastrointestinal Society Survey.1

What can Functional Medicine practitioners do to improve the quality of life and clinical outcomes for these patients? The Functional Medicine model for health care is to understand the underlying factors that contribute to dysfunction and apply treatments that address those causes. In other words, Functional Medicine is concerned less with what we call the dysfunction or disease, and more about the dynamic processes that resulted in the person’s dysfunction.8 While IBS can seem like an intractable problem to patients, many modifiable factors can influence it, including eating habits, diet, exercise, and other lifestyle factors such as stress.7

In the video below, IFM educator Tom Sult, MD, describes his Functional Medicine approach to IBS, which focuses on diet and lifestyle.

Dr. Tom Sult is a graduate of the UCLA School of Medicine and practices Functional Medicine at his clinic in New London, MN.

Diet & IBS

Studies suggest that diets high in fat, carbohydrates, milk products, spicy food, alcohol, and coffee may exacerbate IBS symptoms.4 In fact, surveys on perceived food intolerance show that 64-89% of patients report their symptoms to be triggered by meals or specific foods.4 Using the IFM Elimination Diet may help patients identify food triggers. Both retrospective and prospective open studies have shown reduced IBS symptoms after introduction of a low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (low-FODMAP) diet in patients with suspected or proven fructose or lactose malabsorption.4

A 2019 systematic review and meta-analysis of case-controlled studies points to what Functional Medicine clinicians have been hypothesizing for years—that the gut microbiota plays a key role in disease pathogenesis of IBS.9 Prospective, large-scale studies are needed to delineate how gut microbial profiles can be used to guide targeted therapies.9 The use of probiotics in the diet to help improve IBS symptoms has also been studied, and while the exact mechanisms of probiotics in the body are not fully understood, some research suggests that probiotics may improve IBS symptoms through manipulation of the gut microbiota.10 A 2019 systematic review of the literature over the last five years suggests that multi-strain probiotics supplemented over a period of time have the potential to improve IBS symptoms.10

A 2017 meta-analysis provides high-grade evidence for improved general symptom scores among patients with irritable bowel syndrome who have maintained a low-FODMAP diet compared to those on a traditional IBS diet.11 Interest in the role of gluten intolerance (and the possible benefit of a gluten-free diet) in IBS has been increasing in recent years.4 A systematic meta-analysis found a pooled prevalence for celiac disease up to 4% among IBS patients.12

Exercise & Other Lifestyle Modifications

A 2015 study in China found that patients who were physically inactive were about 3.6 times more likely to suffer from IBS than those who were physically active.13 This accords with an earlier study, published in 2011, that found that increased physical activity improves gastrointestinal symptoms in IBS, and suggests that exercise should be used as a primary treatment modality.14

In 2018, a study of 683 patients with IBS from 14 randomized controlled trials suggested that exercise interventions like yoga, walking/aerobic activity, tai ji, mountaineering, and Baduanjin quigong activity had significant benefits for patients with IBS.15

New studies suggest that cognitive behavioral therapy may also be an effective treatment for sustained gastrointestinal symptom improvement compared with education alone.16 Evidence for using meditation and mindfulness-based therapy in IBS patients is also strong.17,18


Chronic diseases like IBS are often triggered and exacerbated by poor lifestyle choices, and modifications in diet and exercise are generally the first line of treatment in the Functional Medicine model, which seeks to treat the underlying cause of disease. Learn more about IBS in the following IFM-authored articles.

Learn More About Functional Medicine

Stress, bile acids, and IBS symptoms

The gut-brain connection in IBS

Beyond infection: risk factors for IBS


  1. Corsetti M, Tack J, Attara G, Sewell M. IBS Global Impact Report 2018: Uncovering the True Burden of Irritable Bowel Syndrome (IBS) on People’s Lives. Canadian Society of Intestinal Research; 2018. Accessed October 8, 2018.
  2. Corsetti M, Whorwell P. The global impact of IBS: time to think about IBS-specific models of care? Therap Adv Gastroenterol. 2017;10(9):727-736. doi:1177/1756283X17718677
  3. Mönnikes H. Quality of life in patients with irritable bowel syndrome. J Clin Gastroenterol. 2011;45(Suppl):S98-101. doi:1097/MCG.0b013e31821fbf44
  4. Rajili?-Stojanovi? M, Jonkers DM, Salonen A, et al. Intestinal microbiota and diet in IBS: causes, consequences, or epiphenomena? Am J Gastroenterol. 2015;110(2):278-287. doi:1038/ajg.2014.427
  5. Hulisz D. The burden of illness of irritable bowel syndrome: current challenges and hope for the future. J Manag Care Pharm. 2004;10(4):299-309. doi:18553/jmcp.2004.10.4.299
  6. Törnblom H, Emmanuel A, Goosey R, Wiseman G, Baker S. Understanding symptom burden and attitudes in patients with irritable bowel syndrome with diarrhea: results from a patient survey. Gastroenterology. 2017;152(5):S745-S746. doi:1016/S0016-5085(17)32588-X
  7. Miwa H. Life style in persons with functional gastrointestinal disorders—large-scale internet survey of lifestyle in Japan. Neurogastroenterol Motil. 2012;24(5):464-471,e217. doi:1111/j.1365-2982.2011.01872.x
  8. Bland J. Defining function in the functional medicine model. Integr Med. 2017;16(1):22-25.
  9. Wang L, Alammar N, Singh R, et al. Gut microbial dysbiosis in the irritable bowel syndrome: a systematic review and meta-analysis of case-control studies. J Acad Nutr Diet. Published online August 28, 2019. doi:1016/j.jand.2019.05.015
  10. Dale HF, Rasmussen SH, Asiller ÖÖ, Lied GA. Probiotics in irritable bowel syndrome: an up-to-date systematic review. Nutrients. 2019;11(9):E2048. doi:3390/nu11092048
  11. Varjú P, Farkas N, Hegyi P, et al. Low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet improves symptoms in adults suffering from irritable bowel syndrome (IBS) compared to standard IBS diet: a meta-analysis of clinical studies. PLoS One. 2017;12(8):e0182942. doi:1371/journal.pone.0182942
  12. Ford AC, Chey WD, Talley NJ, Malhotra A, Spiegel BM, Moayyedi P. Yield of diagnostic tests for celiac disease in individuals with symptoms suggestive of irritable bowel syndrome: systematic review and meta-analysis. Arch Intern Med. 2009;169(7):651-658. doi:1001/archinternmed.2009.22
  13. Guo YB, Zhuang KM, Kuang L, Zhan Q, Wang XF, Liu SD. Association between diet and lifestyle habits and irritable bowel syndrome: a case-control study. Gut Liver. 2015;9(5):649-656. doi:5009/gnl13437
  14. Johannesson E, Simrén M, Strid H, Bajor A, Sadik R. Physical activity improves symptoms in irritable bowel syndrome: a randomized controlled trial. Am J Gastroenterol. 2011;106(5):915-922. doi:1038/ajg.2010.480
  15. Zhou C, Zhao E, Li Y, Jia Y, Li F. Exercise therapy of patients with irritable bowel syndrome: a systematic review of randomized controlled trials. Neurogastroenterol Motil. 2019;31(2):e13461. doi:1111/nmo.13461
  16. Lackner JM, Jaccard J, Keefer L, et al. Improvement in gastrointestinal symptoms after cognitive behavior therapy for refractory irritable bowel syndrome. Gastroenterology. 2018;155(1):47-57. doi:1053/j.gastro.2018.03.063
  17. Asare F, Störsrud S, Simrén M. Meditation over medication for irritable bowel syndrome? On exercise and alternative treatments for irritable bowel syndrome. Curr Gastroenterol Rep. 2012;14(4):283-289. doi:1007/s11894-012-0268-2
  18. Berrill JW, Sadlier M, Hood K, Green JT. Mindfulness-based therapy for inflammatory bowel disease patients with functional abdominal symptoms or high perceived stress levels. J Crohns Colitis. 2014;8(9):945-955. doi:1016/j.crohns.2014.01.018

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