According to research reviewed by Gram, a 2026 BMJ Open protocol describes a planned randomised controlled trial comparing a low-FODMAP diet with exposure-based cognitive behavioural therapy for irritable bowel syndrome. No results are available yet, so neither treatment has been shown to be better.
Irritable bowel syndrome (IBS) causes stomach pain, bloating, and bowel changes, and people often try different treatments with mixed results. A newly published study protocol in BMJ Open describes a planned randomised controlled trial that will compare two approaches: a low-FODMAP diet, which limits certain hard-to-digest carbohydrates, and exposure-based cognitive behavioural therapy, which helps people face and reduce fear of symptoms. The protocol is a plan for the study, so it does not yet report results. Its goal is to find out which treatment works best and for which types of people. According to research reviewed by Gram, this kind of trial could help doctors and patients choose treatments more wisely, but the answers will only be known once the trial is completed and published.
Key Statistics
A 2026 study protocol published in BMJ Open describes a randomised controlled trial that will compare an internet-delivered low-FODMAP diet with exposure-based cognitive behavioural therapy for irritable bowel syndrome.
Because the 2026 BMJ Open publication is a protocol rather than a completed trial, it reports no measured outcomes, and its results remain unknown until the trial is finished and published.
The Quick Take
- What they studied: Researchers want to know whether a special diet or a type of talk therapy helps people with irritable bowel syndrome more, and whether the answer depends on the person.
- Who participated: The protocol describes adults with irritable bowel syndrome who would be randomly assigned to one of two treatments. The exact number of participants is not stated in the published protocol summary.
- Key finding: This is a study plan, not a completed study, so no results are available yet. The trial is designed to compare the two treatments fairly by assigning people to them by chance.
- What it means for you: If you have IBS, you cannot yet rely on this trial for treatment decisions. Talk with a doctor or dietitian before changing your diet or starting therapy, and watch for results when the study is published.
The Research Details
This is a protocol, which is a detailed written plan that describes how a study will be carried out before any participants are enrolled or any data are collected. Publishing a protocol in advance helps show what researchers intend to measure, which reduces the chance that they change their goals after seeing the results.
The planned study is a randomised controlled trial. In this type of study, participants are assigned to treatment groups by chance, much like drawing names from a hat. Chance assignment helps make the groups similar at the start, so any differences that appear later are more likely caused by the treatments themselves.
The two treatments are delivered over the internet. The low-FODMAP diet limits certain carbohydrates that some people digest poorly. Exposure-based cognitive behavioural therapy teaches people to gradually face situations and sensations they fear, which may reduce how strongly symptoms affect daily life. The study also aims to examine which people respond best to each approach.
Irritable bowel syndrome has no single cure, and people often try several treatments with uneven results. A randomised design is one of the strongest ways to test whether a treatment truly helps, because it separates the effect of the treatment from other factors such as expectations or changes in daily habits.
Comparing two very different approaches in the same trial also helps show which one works better overall. Looking at which people respond best could help match treatments to individuals rather than applying one approach to everyone.
Publishing a protocol in a peer-reviewed journal such as BMJ Open is a positive sign of transparency, because the plan is public before the results exist. However, a protocol cannot show whether the treatments work. Readers should wait for the completed trial report, which will include the final number of participants, the measured outcomes, and any changes made to the original plan.
What the Results Show
This protocol does not report any findings. It describes how researchers plan to measure outcomes such as symptom severity and how much each treatment affects daily life. Symptom severity is usually tracked with standard questionnaires completed by participants over time.
Because the trial compares two different treatments, the main question is which one leads to greater improvement. The trial also aims to explore whether certain traits, such as symptom type or previous experiences, predict who benefits most from each approach.
Until the trial is finished, no conclusions can be drawn about whether either treatment is effective. Any claims about results would be premature.
The protocol also points to broader questions, such as whether internet-delivered treatments are practical and acceptable for people with IBS. Delivering care online may make treatment easier to access for people who live far from specialists, but the trial will need to show whether the approach works in real life.
It may also examine how long any benefits last after treatment ends. Knowing whether improvements persist is important for judging the value of a treatment.
Previous research has suggested that low-FODMAP diets can help many people with IBS, and that cognitive behavioural approaches can also reduce symptoms. However, these two approaches have rarely been compared directly in the same trial. This planned study addresses that gap by testing both under similar conditions and looking at differences between people.
Because this is a protocol, its limitations are mostly about what is still unknown. The final number of participants, the length of follow-up, and the completion rate are not yet available. Internet-delivered treatments may also work differently for people who are less comfortable with technology or who have limited internet access.
It is also possible that the trial will not find a clear winner. Even a well-designed study may show small or mixed differences, which would still be useful but would not give a simple answer.
The Bottom Line
No treatment recommendations can be made from this protocol alone. Current guidance from healthcare professionals often includes trying dietary changes, stress management, and other evidence-based approaches under medical supervision. Confidence in any specific recommendation should wait for the completed trial results.
People living with irritable bowel syndrome, their families, and clinicians who treat them may find this research relevant because it addresses a common problem with limited clear answers. Researchers in digestive health and behavioural medicine will also want to follow the results. People without IBS symptoms do not need to act on this protocol.
A protocol describes a study that has not yet been completed. Trials of this kind typically take months to years to enroll participants, deliver treatments, collect follow-up data, and publish results. Anyone interested should expect to wait for the full report before judging whether either treatment is helpful.
Frequently Asked Questions
Is there a proven treatment for irritable bowel syndrome?
Several approaches are used, including dietary changes and therapy, but no single treatment works for everyone. A 2026 BMJ Open protocol plans to compare two options directly, so clearer answers about which works best are still pending.
What is a low-FODMAP diet?
A low-FODMAP diet limits certain carbohydrates that some people digest poorly, such as some fruits, vegetables, and grains. It is usually followed for a short time under professional guidance and then adjusted based on symptom response.
Can therapy help with irritable bowel syndrome symptoms?
Cognitive behavioural approaches aim to reduce how strongly symptoms affect daily life by changing fear and avoidance patterns. A planned 2026 trial in BMJ Open will test one such approach, exposure-based therapy, against a diet, but results are not yet available.
Where can I find the results of the IBS diet versus therapy study?
The 2026 publication in BMJ Open is a study protocol that describes the trial plan, so results are not included. Look for the completed trial report in the same journal once data collection and analysis are finished.
Want to Apply This Research?
- Log daily symptom severity on a simple 0 to 10 scale, along with bloating, pain, and bowel habit changes such as the number of bowel movements per day and their consistency. Record meals and any foods that seem to trigger symptoms, so patterns can be reviewed with a healthcare provider.
- If you are already working with a dietitian or doctor, use the app to track your meals and symptoms for two to four weeks before making any major change. This creates a baseline that makes it easier to see whether a change helps. Do not start restrictive diets on your own without professional guidance.
- Review symptom and food logs weekly, then look at monthly trends over several months. Share summaries with your healthcare team at regular visits. Once the trial results are published, compare any findings with your own patterns to decide whether they seem relevant to you.
This article summarises a study protocol, a plan for a clinical trial that has not yet produced results. It is for general information only and is not medical advice. Irritable bowel syndrome symptoms can overlap with other conditions, so consult a qualified healthcare professional before changing your diet, starting therapy, or stopping any medication.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.