Irritable Bowel SyndromeNCT05985018
Traditional Dietary Advice Vs. Mediterranean Diet in IBS
A study testing Traditional Diet and Mediterranean Diet in people with Irritable Bowel Syndrome, run by Sheffield Teaching Hospitals NHS Foundation Trust at 1 site in United Kingdom.
Trial summary
Irritable bowel syndrome (IBS) affects 5-10% of the population, and incurs substantial health impairment and healthcare utilization. Over 80% of individuals with IBS report food to trigger or aggravate symptoms, with many seeking to undertake dietary modifications. Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Irritable Bowel Syndrome
- What is being tested?
- Traditional Diet and Mediterranean Diet
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 139 participants
- Where
- 1 siteUnited Kingdom
- Study dates
- 30 Sep 2023to 20 Dec 2024
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- IBS Symptom Severity Scale(IBS-SSS) > 75
- Online access
- English literate
Who cannot join
- Organic gastrointestinal diseases (e.g. inflammatory bowel disease, GI cancer, coeliac disease, microscopic colitis, bile acid diarrhoea)
- Major abdominal surgery (except laparoscopy, appendectomy, cholecystectomy)
- History of eating disorder
- Body mass index <20
- Current dietary interventions
- Current use of opioids/antibiotics
Show all 12Show fewer
- Titrating dose of neuromodulators
- Severe systemic disease (e.g. cardiac, renal, respiratory, psychiatric) necessitating frequent medical consultations/hospitilisations
- Pregnant
- Diabetes mellitus
- Scleroderma
- Memory impairment
Trial locations and contacts
1 site in 1 country.
United Kingdom1 site
Royal Hallamshire Hospital
Sheffield, South Yorkshire, S10 2JF
About this study
Official title: A Randomized Trial of Traditional Dietary Advice Versus Mediterranean Diet in Irritable Bowel Syndrome
Irritable bowel syndrome (IBS) affects 5-10% of the population, and incurs substantial health impairment and healthcare utilization. Over 80% of individuals with IBS report food to trigger or aggravate symptoms, with many seeking to undertake dietary modifications. Current guidelines recommend first-line therapy with the relatively straightforward traditional dietary advice, with the more complex and restrictive low FODMAP diet reserved as second-line therapy.
There is emerging data suggesting that the Mediterranean diet may also improve the symptoms of IBS, although it has not yet been subject to any head-to-head randomized dietary trials to help position it within the treatment algorithm. Given the relative ease of implementing the Mediterranean diet, alongside its recognized cardio-metabolic and mental health benefits, studying its efficacy in IBS is attractive as it could potentially pave the way for another first-line dietary option being available to patients before escalating to the demanding and resource intensive second-line therapies.
The investigators will perform a randomized trial comparing the clinical efficacy of traditional dietary advice vs. a Mediterranean diet in IBS. Following dietary randomization, participants will complete validated questionnaires to assess changes in IBS symptoms, quality of life, mood, somatic symptoms, nutritional status, as well as dietary satisfaction and adherence.
- Conditions
- Irritable Bowel Syndrome
- Being tested
- Traditional Diet, Mediterranean Diet
- Medical subject headings
- Irritable Bowel Syndrome
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Traditional DietOther
Provided as an educational leaflet
Mediterranean DietOther
Provided as an educational leaflet
| Study group | Role | What they receive |
|---|---|---|
| Traditional Dietary Advice | Active comparator | Its main elements are to adopt sensible eating habits and avoid excess fatty foods, spicy foods, processed foods, caffeine, fizzy drinks and alcohol. Receives: Other: Traditional Diet |
| Mediterranean Diet | Active comparator | The principle components is a diet rich in vegetables, pulses, whole grains, and olive oil Receives: Other: Mediterranean Diet |
What is being measured
The primary outcome is the main question the study is designed to answer.
Proportion of IBS patients experiencing clinical response with traditional dietary advice vs. Mediterranean diet
IBS symptom severity scale (IBS-SSS) where a 50-point reduction denotes a meaningful clinical response
Measured: Baseline to Week 6
Secondary outcomes (7)
Changes in individual items of the IBS-SSS
IBS- SSS contains 5 specific questions (pain severity, pain frequency, abdominal distension severity, bowel movement satisfaction, quality of life) with score ranging from 0-100. Change in individual items will be compared within- and between- groups.
Measured: Baseline to Week 6
Changes in Anxiety and Depression
The four-item patient health questionnaire (PHQ-4) for anxiety and depression is a validated questionnaire assessing mood, with higher scores representing worse mood. Change in scores will be compared within- and between- groups
Measured: Baseline to Week 6
Changes in Somatic Symptom reporting
The validated patient health questionnaire-12 assess extra-intestinal somatic symptoms, with higher scores representing greater somatic symptom severity. Change in scores will be compared within- and between- groups
Measured: Baseline to Week 6
Changes in quality of life
The validated Short form 8 Quality of life Questionnaire assesses quality of life, with higher scores representing better quality of life. Change in scores will be compared within- and between- groups
Measured: Baseline to Week 6
Dietary satisfaction to assigned intervention
The Diet Satisfaction Score is a 10-item questionnaire assessing dietary satisfaction to an allocated diet (either Mediterranean diet or traditional diet), with higher scores representing greater satisfaction. Changes in score will be compared between the groups.
Measured: Week 6
Adherence to the Mediterranean diet
The 14-point Mediterranean Diet Adherence Screener will check adequate dietary adherence, which we expect will be seen in those assigned a Mediterranean diet compared with traditional diet. Higher scores represent better adherence.
Measured: Week 6
Changes in nutritional intake
The Comprehensive Nutritional Assessment Questionnaire assesses macronutrient and micronutrient intake, FODMAPs, fibre, starch, glycaemic index/load. Change in scores will be compared within- and between- groups. Only a subset will complete this
Measured: Baseline to Week 6
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Aug 2023
- Study start30 Sep 2023
- Primary completion20 Dec 2024
- Study completion20 Dec 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Irritable Bowel SyndromeStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 139 participants (actual)
Sponsor and investigators
- Lead sponsor
- Sheffield Teaching Hospitals NHS Foundation Trust
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Imran Aziz, Principal investigator, Sheffield Teaching Hospitals NHS Foundation Trust
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05985018
- Sponsor's protocol ID
- STH20655b
- Status last verified
- Mar 2025
- First submitted
- 25 Jul 2023
- Last updated
- 14 Mar 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Bamidele JO, Brownlow GM, Flack RM, Buckle RL, Shaw CC, Shiha MG, Aziz I. The Mediterranean Diet for Irritable Bowel Syndrome : A Randomized Clinical Trial. Ann Intern Med. 2025 Dec;178(12):1709-1717. doi: 10.7326/ANNALS-25-01519. Epub 2025 Oct 28.
PubMed 41144975
Study at a glance
From the registry record, last updated by the sponsor on 14 Mar 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Randomized Trial of Traditional Dietary Advice Versus Mediterranean Diet in Irritable Bowel Syndrome
- ClinicalTrials.gov ID
- NCT05985018
- Acronym / sponsor ID
- STH20655b
- Conditions
- Irritable Bowel Syndrome
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 139 participants (actual)
- Lead sponsor
- Sheffield Teaching Hospitals NHS Foundation TrustUniversity, hospital or other
- Study start
- 30 Sep 2023 (actual)
- Primary completion
- 20 Dec 2024 (actual)
- Study completion
- 20 Dec 2024 (actual)
- First posted
- 9 Aug 2023 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Irritable bowel syndrome (IBS) affects 5-10% of the population, and incurs substantial health impairment and healthcare utilization. Over 80% of individuals with IBS report food to trigger or aggravate symptoms, with many seeking to undertake dietary modifications. Current guidelines recommend first-line therapy with the relatively straightforward traditional dietary advice, with the more complex and restrictive low FODMAP diet reserved as second-line therapy.
There is emerging data suggesting that the Mediterranean diet may also improve the symptoms of IBS, although it has not yet been subject to any head-to-head randomized dietary trials to help position it within the treatment algorithm. Given the relative ease of implementing the Mediterranean diet, alongside its recognized cardio-metabolic and mental health benefits, studying its efficacy in IBS is attractive as it could potentially pave the way for another first-line dietary option being available to patients before escalating to the demanding and resource intensive second-line therapies.
The investigators will perform a randomized trial comparing the clinical efficacy of traditional dietary advice vs. a Mediterranean diet in IBS. Following dietary randomization, participants will complete validated questionnaires to assess changes in IBS symptoms, quality of life, mood, somatic symptoms, nutritional status, as well as dietary satisfaction and adherence.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Traditional Dietary Advice | Active comparator | Other: Traditional DietIts main elements are to adopt sensible eating habits and avoid excess fatty foods, spicy foods, processed foods, caffeine, fizzy drinks and alcohol. |
| Mediterranean Diet | Active comparator | Other: Mediterranean DietThe principle components is a diet rich in vegetables, pulses, whole grains, and olive oil |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- IBS Symptom Severity Scale(IBS-SSS) > 75
- Online access
- English literate
Key exclusion criteria (12 listed)
- Organic gastrointestinal diseases (e.g. inflammatory bowel disease, GI cancer, coeliac disease, microscopic colitis, bile acid diarrhoea)
- Major abdominal surgery (except laparoscopy, appendectomy, cholecystectomy)
- History of eating disorder
- Body mass index <20
- Current dietary interventions
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Traditional DietProvided as an educational leaflet | Other | Traditional Dietary Advice |
| Mediterranean DietProvided as an educational leaflet | Other | Mediterranean Diet |
Primary outcome
Proportion of IBS patients experiencing clinical response with traditional dietary advice vs. Mediterranean diet
Time frame: Baseline to Week 6
IBS symptom severity scale (IBS-SSS) where a 50-point reduction denotes a meaningful clinical response
7 secondary outcomes
Changes in individual items of the IBS-SSS
Time frame: Baseline to Week 6
Changes in Anxiety and Depression
Time frame: Baseline to Week 6
Changes in Somatic Symptom reporting
Time frame: Baseline to Week 6
Changes in quality of life
Time frame: Baseline to Week 6
Dietary satisfaction to assigned intervention
Time frame: Week 6
Adherence to the Mediterranean diet
Time frame: Week 6
Changes in nutritional intake
Time frame: Baseline to Week 6
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 14 Mar 2025.
- Derived from this study: PubMed 41144975Bamidele JO, Brownlow GM, Flack RM, Buckle RL, Shaw CC, Shiha MG, Aziz I. The Mediterranean Diet for Irritable Bowel Syndrome : A Randomized Clinical Trial. Ann Intern Med. 2025 Dec;178(12):1709-1717. doi: 10.7326/ANNALS-25-01519. Epub 2025 Oct 28.
- Individual participant dataSharing planned: No
Related trials for Irritable Bowel Syndrome
RecruitingObservational study
Abdominal Symptoms and Rosacea: An Observational Study on the Association Between Irritable Bowel Syndrome (IBS) and the Gut-Skin Axis
IBS (Irritable Bowel Syndrome), Rosacea
Recruiting
Stress Reduction and Lifestyle Modification in Irritable Bowel Syndrome Patients
Irritable Bowel Syndrome
Recruiting
Exercise Interventions and Dietary Advice in Fibromyalgia and IBS
Fibromyalgia, Irritable Bowel Syndrome
RecruitingPhase 2
A Study of Brenipatide (LY3537031) in Participants With Irritable Bowel Syndrome-Constipation (IBS-C)
Irritable Bowel Syndrome, Constipation
RecruitingPhase 2
A Study of Brenipatide (LY3537031) in Participants With Irritable Bowel Syndrome-Diarrhea (IBS-D)
Irritable Bowel Syndrome, Diarrhea
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Imran Aziz principal investigator
Sheffield Teaching Hospitals NHS Foundation Trust
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Traditional Diet and Mediterranean Diet in people with Irritable Bowel Syndrome, run by Sheffield Teaching Hospitals NHS Foundation Trust at 1 site in United Kingdom.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 12 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 14 Mar 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Proportion of IBS patients experiencing clinical response with traditional dietary advice vs. Mediterranean diet (time frame: Baseline to Week 6). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05985018, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 14 Mar 2025.