Other disorders may contribute to the condition

By David Dunaief, M.D.

If you are among the estimated 10 to 15 percent of the population that suffer from irritable bowel syndrome (IBS) symptoms, managing them can be all-consuming (1). IBS symptoms, which can include abdominal pain, cramping, bloating, constipation and/or diarrhea, have a direct effect on your quality of life.

While there is no single test that provides an IBS diagnosis, physicians eliminate other possibilities and use specific criteria to provide a diagnosis.

The Rome IV criteria are an international effort to help diagnose and treat disorders of gut-brain interaction (2). Using these criteria, which include questions about the frequency of pain over the past three months alongside a physical exam, helps provide a diagnosis.

Once diagnosed, first-line treatment typically involves lifestyle modifications, including dietary changes. Let’s look at what the research tells us.

Is IBS affected by mental state?

The “brain-gut” connection refers to the direct connection between mental state, such as nervousness or anxiety, to gastrointestinal issues, and vice versa.

Mindfulness-based stress reduction was used in a small, but randomized, eight-week clinical trial with IBS (3). Those in the mindfulness group (treatment group) showed statistically significant results in decreased severity of symptoms compared to the control group, both immediately after training and three months post-therapy.

Those in the treatment group were instructed to do meditation, gentle yoga and “body scanning” — focusing on one area of the body for muscle tension detection. The control group attended an IBS support group once a week.

A subsequent meta-analysis of six randomized controlled trials (RCTs) that studied the effects of mindfulness on IBS found that the combined study group achieved improved quality of life and lower pain scores, perceived stress anxiety, and visceral sensitivity than the control group (4).

Interestingly, a 2021 international study of more than 50,000 participants found that there were some genetic similarities among those who suffer from IBS and those who suffer from common mood and anxiety disorders such as anxiety, depression, and neuroticism, as well as insomnia. As the authors wrote, “Although IBS occurs more frequently in those who are prone to anxiety, we don’t believe that one causes the other – our study shows these conditions have shared genetic origins, with the affected genes possibly leading to physical changes in brain or nerve cells that in turn cause symptoms in the brain and symptoms in the gut” (5). In other words, they may have a common cause.

Is gluten a factor?

Gluten sensitivity may be an important factor for some IBS patients (6).

In a small randomized clinical trial, patients who were given gluten were more likely to complain of uncontrolled symptoms than those who were given a placebo, 68 percent vs. 40 percent, respectively (7). These results were highly statistically significant, and the authors concluded that nonceliac gluten intolerance may exist. 

What role does fructose play?

Some IBS patients may suffer from fructose intolerance. In a study, IBS researchers used a breath test to explore this possibility (8). The results were dose-dependent, meaning the higher the dose of fructose, the greater the effect researchers saw. When patients were given a 10 percent fructose solution, only 39 percent tested positive for fructose intolerance, but when they were given a 33 percent solution, 88 percent of patients did.

The symptoms of fructose intolerance included gas, abdominal pain, bloating, belching and alternating bowel habits. The authors concluded that fructose avoidance may reduce symptoms in some IBS sufferers.

According to another study, about one-third of IBS patients are fructose intolerant. When on a fructose-restricted diet, symptoms appeared to improve (9). Foods with high levels of fructose include certain fruits, like apples and pears.

Is lactose intolerance a contributor?

According to another small study, about one-quarter of patients with IBS also have lactose intolerance (10). 

Of the IBS patients who were also lactose intolerant, there was a marked improvement in symptoms at both six weeks and five years when placed on a lactose-restricted diet.

Though the trial was small, the results were statistically significant. Both the patient compliance and long-term effects were excellent, and outpatient clinic visits were reduced by 75 percent.

Will probiotics help?

A study that analyzed 42 trials focused on treatment with probiotics shows there may be a benefit to probiotics, although each trial’s objectives, or endpoints, were different (11).

Probiotics do show promise, including the two most common strains, Lactobacilli and Bifidobacteri, which were covered in the review.

All of these studies provide hope for IBS patients — and the research is continuing with assessments of peppermint oil consumption and gut-directed hypnotherapy, among others. Since the causes can vary, a strong patient-doctor relationship can assist in selecting an approach that provides the greatest relief for each patient’s symptoms.

References:

(1) American College of Gastroenterology [GI.org]. (2) J Neurogastroenterol Motil. 2017 Apr; 23(2): 151–163. (3) Am J Gastroenterol. 2011 Sep;106(9):1678-1688. (4) J Clin Med. 2022 Nov; 11(21): 6516. (5) Nat Genet 53, 1543–1552 (2021). (6) Am J Gastroenterol. 2011 Mar;106(3):516-518. (7) Am J Gastroenterol. 2011 Mar;106(3):508-514. (8) Am J Gastroenterol. 2003 June; 98(6):1348-1353. (9) J Clin Gastroenterol. 2008 Mar;42(3):233-238. (10) Eur J Gastroenterol Hepatol. 2001 Aug;13(8):941-944. (11) Aliment Pharmacol Ther. 2012 Feb;35(4):403-413.

Dr. David Dunaief is a speaker, author and local lifestyle medicine physician focusing on the integration of medicine, nutrition, fitness and stress management. For further information, visit www.medicalcompassmd.com or consult your personal physician.