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Irritable Bowel Syndrome (IBS)

Irritable bowel syndrome (IBS) is influenced by many factorsneurological, immunological, psychological, and likely others. The following offers evidence-based suggestions for a Whole Health approach to IBS, recognizing that no one intervention is effective or curative for everyone; pharmaceuticals are no exception. Successfully treating IBS requires one to approach this complex and dynamic interplay on a case-by-case basis. A continuous therapeutic relationship is essential. Because of the lack of consistent effectiveness of pharmaceuticals, nearly 40% of those with IBS turn to other therapeutic options.[1] These are discussed below.

IBS is an alarmingly common condition in the U.S. military population, with estimates of up to one-third of military women having this syndrome.[2] Rates in men have not been well characterized in the military population but are thought to be much lower. Women, specifically, experience a considerable decrease in quality of life due to this condition, making effective treatment a high priority.[3]

IBS is often associated with comorbidities, including posttraumatic stress disorder (PTSD), depression, and anxiety.[4] A history of sexual trauma is even more strongly associated with IBS than any mood disorder.[2] IBS is also more common in those who have suffered some sort of hit that throws the ecosystem of their GI tract out of balance. Examples include infections (e.g., travelers diarrhea), medication use (antibiotics, steroids, chemotherapy), and significant emotional stressors. A clinician should address potential chronic sequelae of these hits to determine how best to bring this dynamic ecosystem back into balance.[5]

Research for the Circle of Health items as they relate to IBS is summarized below.

Moving the Body

Regular physical activity has a positive impact on nearly all diseases, especially those with a strong mind-body component. The positive effect of movement on IBS symptoms likely stems from the stress-relieving and bowel motility benefits it confers. Mild physical exercise has been found to increase gas clearance and reduce bloating.[6] Women who are more physically active tend to have fewer and less severe IBS symptoms.[7] One small randomized controlled trial showed that increasing physical activity had symptomatic benefits in those with constipation-predominant IBS.[8] Despite these demonstrated benefits of exercise on IBS symptoms, research does not support alternative exercise recommendations for those with IBS versus the general population.


Several studies have shown positive results with various types of yoga, particularly pranayama, a form of yoga that focuses on the breath. Pranayama breathing stimulates the parasympathetic autonomic system, which mediates relaxation of intestinal spasm through the vagus nerve. A 2-month study showed that twice-daily yoga was equivalent to loperamide in those with diarrhea-predominant IBS symptoms.[9] A systematic review supports increases in quality of life, improved anxiety, and decreased symptoms, but it was no more effective than daily walking to meet general exercise recommendations. [10]

Food & Drink

The first-line approach to diet should not differ between those with or without IBS. Given that most Americans do not adhere to general dietary guidelines, these recommendations should serve as a starting point. Further, those with IBS may be particularly sensitive to excessive consumption of alcohol, spicy foods, caffeine, and dietary fat, and inadequate consumption of hydrating fluids.[11]

Elimination diets

Individuals with IBS may be particularly sensitive to intestinal gas accumulation triggered by fermentation of specific types of carbohydrates. For this reason, the Low FODMaP Diet (fermentable oligo-, di, and monosaccharides and polyols) has been developed, and this dietary approach is increasingly becoming a second-line recommendation (after general dietary guidance, above). Refer to The Low FODMaP Diet Whole Health tool, and consider incorporating a simple list of common FODMaP foods.

FODMaP foods all contain short-chain carbohydrates of varying lengths that are often incompletely absorbed by the GI tract. By remaining present in the GI tract rather than being absorbed, these carbohydrates are vulnerable to fermentation by enteric bacteria, producing gas and abdominal distention. Gibson and colleagues found that avoiding foods containing these carbohydrates led to relief in 75% of those with IBS.[12] Newer studies support this dietary approach for only those with diarrhea or mixed IBS subtypes (not constipation), and only when led by a dietician; giving brief instruction and handouts have proved less effective[11] and possibly less safe.

A third-line dietary approach is a more targeted and personalized elimination diet. This may include selecting a few or more foods that are high in FODMaPs or as guided by an individuals experiences and intuition. (To learn more, review the Elimination Diets Whole Health tool.) Several controlled studies have shown that people who based an elimination diet on IgG results improved more than those who eliminated random foods.[13][14] However, IgG testing (as opposed to IgE) is not widely available, and studies have been small and of low quality; therefore, incorporating IgG testing should be reserved as a fourth-line option if a more personalized elimination diet is not effective. More about various GI tests is available in the Testing to Assess the Gastrointestinal Ecosystem Whole Health tool.

It is worth noting that many individuals consider eliminating gluten to improve their symptoms as a part of an elimination diet. While a review of gluten intolerance is beyond the scope of this resource, wheat, barley, and rye make up about 50% of the FODMaPs in the average Americans diet. Several well-controlled studies have shown that people who based an elimination diet on IgG results improved more than those who eliminated random foods.[13][14] Therefore, eliminating these common grains may well provide benefits, regardless of a possible mechanism related to gluten.


Fiber maintains a healthy intestinal mucous layer, acts as a prebiotic (a food for probiotic bacteria), and lowers cholesterol. It undergoes fermentation in the colon, leading to gas and short-chain fatty acid production. These characteristics likely improve stool frequency and consistency in those with IBS, but overall, results of studies focused on fiber and IBS are quite mixed.[15] Whether fiber is insoluble or soluble, however, seems to make a difference. Several studies have shown that insoluble fiber (i.e., bran) often worsens symptoms, though this may be due in part to inadequate increases in fluid intake. Other studies show that soluble fiber, at least for those with constipation-type IBD, is likely effective.[9][16][17][18][19][20][21] Good examples of soluble fiber include guar gum (5-10 gm per day), ground flaxseed (1 tbsp once or twice per day), and psyllium husk (1 tbsp in 8 oz of water twice per day). As a general principle, start fiber at low doses, increase slowly, and allow time for an adequate trial (1-2 months).

Power of the Mind

Our GI system, often is referred to as our second brain, rivals the brain in terms of numbers of neural connections and volume of neurotransmitters. However, it may be most useful to consider the brain and GI nervous system as a single unit, given how entwined they are. Their relationship is mediated by the autonomic nervous system, hypothalamic-pituitary axis, and the immune system. Problematic thoughts and emotions can manifest as abdominal pain, bloating, and spasms. This interplay has given rise to many common metaphors, such as I have butterflies in my stomach. It is worth listening for such statements as clues to how best to work with people with IBS.

Individuals with IBS have increased perception of stress, and this can chronically affect their symptoms. Furthermore, IBS sufferers are hyper-vigilant regarding body sensations.[22] The power of the mind can be a therapeutic tool for IBS in the following ways:

Cognitive behavioral therapy

Cognitive Behavioral Therapy (CBT) focuses on identifying behaviors and thought patterns, as well as negative emotions that hinder progress toward ones self-defined goals. [22][23] This mind-body modality has the most robust evidence base for improvements in function.[24][25] Some data suggests that online delivery may be as effective as live delivery, which may allow systems to greatly expand this underutilized service. [24]


Hypnotherapy is a method of deliberately using verbal cues to induce an altered state of awareness for a targeted therapeutic indication. These verbal cues can enhance relaxation, the ability to generate imagery, and focus. Evidence supports the use of either Gut-Directed Hypnotherapy (GDH) or audiotape hypnotherapy, and one trial found these equally effective for IBS with response rates of 50%-75%.[26] GDH is more resource intensive than a self-directed audiotape, requiring 8-12 sessions that are one-half to 1 hour long. Several studies showed that hypnotherapy seems to have consistent positive effects on IBS, with an estimated 25-73% improvement in bowel symptoms, psychological distress, and quality of life that lasted over a year after treatment was completed.[27][28][29] In refractory cases referred to a GI clinic, an uncontrolled prospective study of 204 individuals found that 81% received benefit; 71% of these continued to have benefits 5 years later.[30] Although larger randomized trials are needed to verify the effectiveness of hypnotherapy, its safety and potential benefit makes it a worthwhile therapeutic option. It also remains unclear how this intervention compares to others.

For self-guided hypnosis audio resources, visit Health Journeys website. For a copy of a script you can use for yourself or with patients to ease abdominal pain, refer to the Whole Health tool, Balloon Self-Hypnosis Technique for IBS and Abdominal PainA Guide for Clinicians.

Brief Psychodynamic Psychotherapy

This insight-oriented talk therapy focuses on discussions of symptoms, emotions, and the mind-body connection. It is used extensively in the United Kingdom. Two large studies have yielded positive results. The largest of these included 257 individuals and had control groups that included paroxetine as well as standard medical care. Both the psychotherapy group and the paroxetine group had similar improvements in quality of life, but the psychotherapy group had lower health care costs.[23]


Meditation can be done in many ways, and the goal of all of them is to focus ones attention. Given the role of maladaptive stress in those with IBS, it makes sense that altering ones stress response through meditation can be beneficial. However, to date, no controlled studies have been done. Research does suggest that people with GI symptoms who attend a Mindfulness-Based Stress Reduction (MBSR) course have a reduction of symptoms.[22][31][32] Given the multitude of confirmed and suspected health benefits of meditation, this very safe intervention should be considered for those with IBS.

A note on the placebo response: Placebos can be viewed as proactive healing mechanisms that are stimulated through social support, positive expectation, and hope. One meta-analysis estimates a 40%-50% response rate to these important components of Whole Health.[33][34] Factors associated with higher placebo response rates include longer treatment duration, more office visits, and the overall treatment effect of the agent with which the placebo is being compared.[35] Placebo responses derive from malleable expectations and are not necessarily related to the specific type of treatment; placebo response rates in trials for IBS across modalities show no consistent trends, whether studying a medication, mind-body intervention, or supplement.[36] Given that positive expectations about treatments can be greatly enhanced by therapeutic patient-practitioner relationships, building trust and instilling hope should be key ingredients in any Personal Health Plan (PHP) for someone with IBS.

Dietary Supplements

Note: Please refer to the Passport to Whole Health, Chapter 15 on Dietary Supplements for more information about how to determine whether or not a specific supplement is appropriate for a given individual. Supplements are not regulated with the same degree of oversight as medications, and it is important that clinicians keep this in mind. Products vary greatly in terms of accuracy of labeling, presence of adulterants, and the legitimacy of claims made by the manufacturer.

Peppermint oil

Peppermint is one of the most commonly used supplements for IBS. Its main active ingredient is menthol, an antispasmodic. It works best to treat spasms that lead to abdominal pain as opposed to treating distention and flatulence. It has also been shown to improve diarrhea, constipation, urgency, and incomplete defecation.[37] One systemic review showed response rates in those using peppermint oil of 79% for abdominal pain, 83% for abdominal distention, and 73% for flatulence.[38] These findings are as good as those for pharmaceuticalsif not betterand peppermint oil has fewer side effects. In fact, the number needed to treat (NNT) is 2-3, making this possibly the single, most-effective intervention for IBS.[39]

One common side effect of peppermint is heartburn because it also relaxes the lower esophageal sphincter. Use Peppermint with caution for those with gastroesophageal reflux disease (GERD). An enteric-coated preparation may allow release of the peppermint more distally in the GI tract. Most quality products have at least 44% menthol and less than 1% pulegone (a neuro- and hepatotoxin).[40] A common dose is 0.2 to 0.4 mL three times daily of enteric-coated capsules. Adverse effects are rare.


Increased intestinal permeability and intestinal dybiosis seem to be a part of IBS pathogenesis. Those with IBS have differences in their microbiomes than those without this condition, particularly in those with the diarrhea subtype.[41] Intestinal bacteria directly interact with the intestinal wall to influence how easy or difficult it is for larger molecules to be absorbed from the gut into the bloodstream. An intestine that is too permeable allows macromolecules into the bloodstream, where they are more likely to trigger an immune response than smaller compounds. As macrophages, antibodies, and cytokines mobilize, food intolerances and IBS symptoms can develop.

Probiotics may offer benefit in many ways, including healing the gut mucosal barrier, improving intestinal flora, altering ones immune response, decreasing inflammation, and/or altering fermentation in the intestinal tract. Many studies investigating a wide range of bacterial strains have been performed, and the most positive single-species studies have shown the specific strain Bifidobacterium infantis (B. infantis) 35624 at a dose of 108 colony-forming units (CFUs) to be the most effective.[42][43] However, multi-species probiotics seem to provide superior relief when used for at least eight weeks; these should contain Lactobacillus and at least one of either Streptomyces or Bifidobacterium species.[ ref id=44]

In one meta-analysis, the number of people who needed to be treated (NNT) with probiotics, to have one individual experience improvement, was found to be as low as four.[45] Probiotics have significant favorable effects on abdominal pain, bloating, and bowel movement difficulty, especially in those with the diarrhea subtype.[15][46]

While using probiotics can be helpful, it remains unclear if they provide long-term benefits beyond several months. Some studies suggest that they do not, and other studies suggest that they may possibly worsen symptoms after 3-4 months.[47] Therefore, using probiotics mainly during times of worsening symptoms, while incorporating other modalities, may be the best approach.

Iberogast (STW 5)

Iberogast (STW 5), originally from Germany, is a combination of extracts from nine different herbs. It has been studied for several functional GI disorders. Its contents include the following:

  • Bitter candytuft (Iberis amara) also known as clowns mustard
  • Angelica root (Angelica archangelica)
  • Milk thistle fruit (Silybum marianum)
  • Celandine aerial parts (Chelidonium majus)
  • Caraway fruit (Carum carvi)
  • Licorice root (Glycyrrhiza glabra)
  • Peppermint leaf (Menthae piperitae)
  • Lemon balm leaf (Melissae officinalis)
  • Chamomile flower (Matricaria recutita)

Several studies have shown a benefit over placebo for abdominal pain.[48] The constituents of Iberogast (STW 5) have properties that alter GI motility; many also have anti-inflammatory properties. Its varied mechanisms of action likely explain its wide-ranging effectiveness.[49]

Other Healing Systems


Randomized controlled studies have not shown a clear benefit of acupuncture in reducing symptoms or severity or in improving quality of life. However, a few Chinese trials have shown that acupuncture may be more beneficial than antispasmodic medications. It may be that individuals who prefer acupuncture as a treatment modality, or have greater expectations of improvement with acupuncture, will benefit more from acupuncture than medications.[50][51] In many studies, quality of life improves in both treatment and sham acupuncture groups. Given that acupuncture has a favorable benefit-to-risk ratio, it may be worth considering, though cost and accessibility must also be taken into account.[52]

Summary of Nonpharmaceutical Options for IBS

To receive an A rating, based on the Strength of Recommendation Taxonomy (SORT) criteria, a therapy needs to be supported by a systematic review or meta-analysis showing benefit, a Cochrane review with clear recommendation, or a high-quality, patient-oriented randomized controlled trial.

The following therapies are supported by consistent, good-quality, and patient-oriented evidence and would receive an A rating:

  • Cognitive Behavioral Therapy through health psychology referral; consider other mind-body modalities if not available
  • Probiotics: infantis 35624 (brand name: Align); if not available, consider other Bifidobacterium and/or Lactobacillus species
  • Soluble fiber: psyllium husk, 1 tbsp in 8 oz water twice daily (best evidence); ground flaxseed, 1 tbsp twice daily; guar gum, 5 gm daily
  • FODMaP Diet: should be dietician-guided
  • Peppermint: 0.2-0.4 mL enteric-coated capsules three or four times daily

The following therapies, supported by inconsistent or limited-quality patient-oriented evidence, receive a B rating:

  • Elimination diet: if different from FODMaP; can be empiric or individualized
  • Clinical Hypnosis: GDH by a certified practitioner; if not available, self-hypnosis techniques may be an option
  • Iberogast (STW 5): 20 drops three times daily (before/with meals)
  • Brief Psychodynamic Psychotherapy through a health psychology referral

The following therapies are supported by consensus, usual practice, opinion, disease-oriented evidence or case series and would receive a C rating:

  • Meditation/relaxation: MBSR course; consider other forms of relaxation therapies as available (Guided Imagery, progressive muscle relaxation, breathing exercises)
  • Acupuncture: certified practitioner; consider only recommending to those with positive expectations
  • Physical activity: vigorous activity 30 minutes or more on most days of the week; consider yoga


Irritable Bowel Syndrome was written by David Lessens, MD, MPH (2014, updated 2020). Sections of this Whole Health tool were adapted from An Integrative Approach for Treating Irritable Bowel Syndrome by David Rakel, MD.



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