Irritable Bowel Syndrome (IBS)NCT07619573
EFFECT OF A DİETİTİAN-SUPERVİSED LOW-FODMAP DİET VERSUS STANDARD WRİTTEN ADVİCE ON GASTROİNTESTİNAL SYMPTOMS AND INFLAMMATORY BİOMARKERS İN IRRİTABLE BOWEL SYNDROME: A RANDOMİZED CONTROLLED TRİAL
A study testing Low-FODMAP Diet Intervention in people with Irritable Bowel Syndrome (IBS), run by Biruni University at 2 sites in Turkey (Türkiye).
Trial summary
Background: Irritable Bowel Syndrome (IBS) is the most prevalent functional gastrointestinal (GI) pathology among GI disorders. Various dietary interventions, particularly the low-FODMAP diet, are employed to alleviate IBS symptoms. Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Irritable Bowel Syndrome (IBS)
- What is being tested?
- Low-FODMAP Diet Intervention
- Type of treatment
- Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 50 participants
- Where
- 2 sitesTurkey (Türkiye)
- Study dates
- 1 Apr 2025to 30 Oct 2025
- 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
- Adults aged 18-65 years.
- Diagnosed with IBS according to the Rome IV criteria.
Who cannot join
- Use of antibiotics, NSAIDs, oral contraceptives, or hormone therapy during the study.
- Pregnancy or breastfeeding.
- Diagnosis of celiac disease
Trial locations and contacts
2 sites in 1 country.
Turkey (Türkiye)2 sites
Biruni University Faculty of Medicine Hospital
Istanbul, Istanbul
Biruni University
Istanbul, Istanbul
About this study
Background:
Irritable Bowel Syndrome (IBS) is the most prevalent functional gastrointestinal (GI) pathology among GI disorders. Various dietary interventions, particularly the low-FODMAP diet, are employed to alleviate IBS symptoms.
Read more
Study Population \& Design:
This study will include 78 adult patients, aged 18-65, diagnosed with IBS according to Rome IV criteria at the Biruni University Faculty of Medicine Hospital Gastroenterology Outpatient Clinic. Participants will be divided into two parallel groups:
Group 1 (n=39): Will receive dietary intervention solely through physician follow-up (provided with a standard hospital brochure listing prohibited foods).
Group 2 (n=39): Will receive structured, personalized dietary intervention through individualized nutritional counseling by a dietitian.
Duration: The low-FODMAP diet intervention for both groups will last for 8 weeks.
Outcome Measures:
At baseline (week 0) and at the conclusion of the study (week 8), the following assessments will be conducted:
Clinical Scores: IBS Symptom Severity Score (IBS-SSS) and the 15-item Gastrointestinal Symptom Rating Scale (GSRS).
Biomarkers: Hs-CRP and fecal calprotectin levels analyzed from blood and stool samples.
Objective:
The primary objective is to determine the impact of individualized nutritional counseling on GI symptoms and inflammatory biomarkers (hs-CRP, fecal calprotectin) during a low-FODMAP diet. Secondary objectives include evaluating the significance of the dietitian's role and observing how lifestyle factors (sleep and physical activity) influence symptom outcomes alongside nutritional therapy.
Read the detailed description
The low-FODMAP diet, developed for the treatment of IBS, is defined as a dietary regimen that restricts fermentable oligosaccharides, disaccharides, monosaccharides, and polyols-which are short-chain carbohydrates with limited or poor absorption.
Study Timeline and Interventions:
First Week: A 31-item "Data Collection Form" covering socio-demographic characteristics, health information, and nutritional habits will be administered.
Daily Monitoring: Daily records of the "Bristol Stool Scale" (BSS) will be maintained throughout the study.
Study Duration: The low-FODMAP diet intervention will be implemented for a total duration of 8 weeks.
Face-to-Face Assessments (Conducted at Baseline and Conclusion):
At the beginning and end of the study, the following assessments will be conducted face-to-face with the participants:
- 24-hour Dietary Recall
- Anthropometric measurements
- Frequency of FODMAP-sourced food consumption over the past month
- 7-item "International Physical Activity Questionnaire - Short Form" (IPAQ-SF)
- 5-item "IBS Symptom Severity Score" (IBS-SSS)
- 15-item "Gastrointestinal Symptom Rating Scale" (GSRS)
- 8-item "Epworth Sleepiness Scale" (ESS)
Laboratory Analysis:
Hs-CRP and fecal calprotectin levels will be analyzed from blood and stool samples collected at baseline and at the conclusion of the study.
- Conditions
- Irritable Bowel Syndrome (IBS)
- Being tested
- Low-FODMAP Diet Intervention
- Keywords
- Irritable Bowel Syndrome (IBS), low-FODMAP diet, gastrointestinal symptoms, dietitian
- 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.
Low-FODMAP Diet InterventionBehavioural
This intervention consists of an 8-week low-FODMAP dietary regimen aimed at restricting the intake of short-chain carbohydrates, including fermentable oligosaccharides, disaccharides, monosaccharides, and polyols.
The intervention is administered through two distinct protocols to compare delivery methods: one group receives standard hospital care consisting of a brief physician follow-up accompanied by a standard educational brochure listing prohibited foods, while the other group receives structured, individualized nutritional counseling and personalized meal planning led by a professional dietitian.
| Study group | Role | What they receive |
|---|---|---|
| Dietitian group | Experimental | A dietitian planned the low FODMAP diet for the first group (n=31) through individual dietary counselling. Receives: Behavioral: Low-FODMAP Diet Intervention |
| Doctor group | Active comparator | The second group (n=19) was given a brochure on the low FODMAP diet, as is routine in the hospital, listing foods prohibited by the gastroenterologist. Receives: Behavioral: Low-FODMAP Diet Intervention |
What is being measured
The primary outcome is the main question the study is designed to answer.
IBS-SSS
Irritable Bowel Syndrome Symptom Severity Score (IBS-SSS). The IBS-SSS consists of 5 questions, each scored from 0 to 100, with a maximum possible total score of 500. It determines the severity of abdominal pain, abdominal pain frequency, abdominal bloating severity, satisfaction with bowel habits, and the impact of the disease on quality of life. Total scores are classified as follows: 75-174 points = mild IBS, 175-299 points = moderate IBS, and greater than or equal to 300 points = severe IBS. Higher scores indicate more severe IBS symptoms.
Measured: From enrollment to the end of treatment at 8 weeks
GSRS
Gastrointestinal Symptom Rating Scale (GSRS). The GSRS is a 15-item questionnaire that uses a 5-point Likert scale to assess the severity of gastrointestinal symptoms across 5 subscales: abdominal pain, reflux, diarrhoea, indigestion, and constipation. Scores are aggregated to determine symptom severity, where higher scores represent a higher severity of gastrointestinal symptoms.
Measured: From enrollment to the end of treatment at 8 weeks
Fecal Calprotectin
Fecal calprotectin levels will be analyzed from stool samples collected from participants to evaluate gastrointestinal inflammation.
Measured: From enrollment to the end of treatment at 8 weeks
Hs-CRP
High-Sensitivity C-Reactive Protein (hs-CRP). Hs-CRP levels will be analyzed from blood samples collected from individuals to monitor systemic biochemical findings of inflammation.
Measured: From enrollment to the end of treatment at 8 weeks
Secondary outcomes (5)
Anthropometric measurement data
height in cm, body weight in kg, waist circumference in cm, hip circumference in cm, body composition and bioelectrical impedance analysis (BIA) measurements
Measured: From enrollment to the end of treatment at 8 weeks
IPAQ-SF
The IPAQ-SF is a seven-item measure that assesses individuals\' physical activity levels over the past seven days. The scale inquires about walking, moderate and vigorous physical activities, and time spent sitting, and physical activity level is calculated in MET-minutes per week
Measured: From enrollment to the end of treatment at 8 weeks
Epworth Sleepiness Scale (ESS)
The ESS is an eight-item self-report measure that assesses an individual\'s likelihood of falling asleep in various everyday situations
Measured: From enrollment to the end of treatment at 8 weeks
Data Collection Form
At the beginning of the study, a 31-item Data Collection Form; covering the sociodemographic characteristics, health information and dietary habits of participating patients was administered.
Measured: At the beginning of the study
Daily Total FODMAP Intake
Food consumption records were taken for 3 days before and after the diet. The data was entered into the Bebis program. Food consumption records were calculated using the Nutrition Information System (BeBiS, version 9, Germany) for energy, macronutrients, micronutrients and FODMAP amounts (total FODMAP (g) = lactose (g) + oligosaccharides (g) + mannitol (g) + sorbitol (g)). Free fructose, a monosaccharide, could not be included in this programme as it could not be calculated.
Measured: From enrollment to the end of treatment at 8 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted2 Jun 2026
- Study start1 Apr 2025
- Primary completion1 Oct 2025
- Study completion30 Oct 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Irritable Bowel Syndrome (IBS)Studies of the same condition, open and under way.
- More trials run by Biruni UniversityThe sponsor's other registered studies.
- 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
- Model description
- The patients were randomly assigned to two groups: One group (n=31) followed a low FODMAP diet under the guidance of a dietitian, while the other group (n=19) followed the diet based on a brochure provided by a doctor.
- Masking
- None (open label)
- Enrolment
- 50 participants (actual)
Sponsor and investigators
- Lead sponsor
- Biruni University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Sevde Kahraman, Biruni University
- Investigators
- Sevde KAHRAMAN, Asst. Prof., Study chair, Biruni UniversityZeynep Çavdar, Master's student and dietitan, Study director, Biruni UniversityKoray Koçhan, Specialist of Gastroenterology, Principal investigator, Department of Gastroenterology, Biruni University Faculty of Medicine HospitalHuri Demirci, PhD, Associate Professor, Principal investigator, Biruni UniversityFatma Çelik, PhD, Professor, Study chair, Biruni University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07619573
- Sponsor's protocol ID
- 2015-KAEK-80-23-49/SKLOWFODMAP
- Status last verified
- May 2026
- First submitted
- 26 May 2026
- Last updated
- 2 Jun 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 2 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- EFFECT OF A DİETİTİAN-SUPERVİSED LOW-FODMAP DİET VERSUS STANDARD WRİTTEN ADVİCE ON GASTROİNTESTİNAL SYMPTOMS AND INFLAMMATORY BİOMARKERS İN IRRİTABLE BOWEL SYNDROME: A RANDOMİZED CONTROLLED TRİAL
- ClinicalTrials.gov ID
- NCT07619573
- Acronym / sponsor ID
- 2015-KAEK-80-23-49/SKLOWFODMAP
- Conditions
- Irritable Bowel Syndrome (IBS)
- Keywords
- Irritable Bowel Syndrome (IBS), low-FODMAP diet, gastrointestinal symptoms, dietitian
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 50 participants (actual)
- Lead sponsor
- Biruni UniversityUniversity, hospital or other
- Study start
- 1 Apr 2025 (actual)
- Primary completion
- 1 Oct 2025 (actual)
- Study completion
- 30 Oct 2025 (actual)
- First posted
- 2 Jun 2026 (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.
Background:
Irritable Bowel Syndrome (IBS) is the most prevalent functional gastrointestinal (GI) pathology among GI disorders. Various dietary interventions, particularly the low-FODMAP diet, are employed to alleviate IBS symptoms.
Study Population \& Design:
This study will include 78 adult patients, aged 18-65, diagnosed with IBS according to Rome IV criteria at the Biruni University Faculty of Medicine Hospital Gastroenterology Outpatient Clinic. Participants will be divided into two parallel groups:
Group 1 (n=39): Will receive dietary intervention solely through physician follow-up (provided with a standard hospital brochure listing prohibited foods).
Group 2 (n=39): Will receive structured, personalized dietary intervention through individualized nutritional counseling by a dietitian.
Duration: The low-FODMAP diet intervention for both groups will last for 8 weeks.
Outcome Measures:
At baseline (week 0) and at the conclusion of the study (week 8), the following assessments will be conducted:
Clinical Scores: IBS Symptom Severity Score (IBS-SSS) and the 15-item Gastrointestinal Symptom Rating Scale (GSRS).
Biomarkers: Hs-CRP and fecal calprotectin levels analyzed from blood and stool samples.
Objective:
The primary objective is to determine the impact of individualized nutritional counseling on GI symptoms and inflammatory biomarkers (hs-CRP, fecal calprotectin) during a low-FODMAP diet. Secondary objectives include evaluating the significance of the dietitian's role and observing how lifestyle factors (sleep and physical activity) influence symptom outcomes alongside nutritional therapy.
Detailed description
The low-FODMAP diet, developed for the treatment of IBS, is defined as a dietary regimen that restricts fermentable oligosaccharides, disaccharides, monosaccharides, and polyols-which are short-chain carbohydrates with limited or poor absorption.
Study Timeline and Interventions:
First Week: A 31-item "Data Collection Form" covering socio-demographic characteristics, health information, and nutritional habits will be administered.
Daily Monitoring: Daily records of the "Bristol Stool Scale" (BSS) will be maintained throughout the study.
Study Duration: The low-FODMAP diet intervention will be implemented for a total duration of 8 weeks.
Face-to-Face Assessments (Conducted at Baseline and Conclusion):
At the beginning and end of the study, the following assessments will be conducted face-to-face with the participants:
- 24-hour Dietary Recall
- Anthropometric measurements
- Frequency of FODMAP-sourced food consumption over the past month
- 7-item "International Physical Activity Questionnaire - Short Form" (IPAQ-SF)
- 5-item "IBS Symptom Severity Score" (IBS-SSS)
- 15-item "Gastrointestinal Symptom Rating Scale" (GSRS)
- 8-item "Epworth Sleepiness Scale" (ESS)
Laboratory Analysis:
Hs-CRP and fecal calprotectin levels will be analyzed from blood and stool samples collected at baseline and at the conclusion of the study.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- The patients were randomly assigned to two groups: One group (n=31) followed a low FODMAP diet under the guidance of a dietitian, while the other group (n=19) followed the diet based on a brochure provided by a doctor.
| Arm | Type | Receives |
|---|---|---|
| Dietitian group | Experimental | Behavioral: Low-FODMAP Diet InterventionA dietitian planned the low FODMAP diet for the first group (n=31) through individual dietary counselling. |
| Doctor group | Active comparator | Behavioral: Low-FODMAP Diet InterventionThe second group (n=19) was given a brochure on the low FODMAP diet, as is routine in the hospital, listing foods prohibited by the gastroenterologist. |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (2 listed)
- Adults aged 18-65 years.
- Diagnosed with IBS according to the Rome IV criteria.
Key exclusion criteria (3 listed)
- Use of antibiotics, NSAIDs, oral contraceptives, or hormone therapy during the study.
- Pregnancy or breastfeeding.
- Diagnosis of celiac disease
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 |
|---|---|---|
| Low-FODMAP Diet InterventionThis intervention consists of an 8-week low-FODMAP dietary regimen aimed at restricting the intake of short-chain carbohydrates, including fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. The intervention is administered through two distinct protocols to compare delivery methods: one group receives standard hospital care consisting of a brief physician follow-up accompanied by a standard educational brochure listing prohibited foods, while the other group receives structured, individualized nutritional counseling and personalized meal planning led by a professional dietitian. | Behavioural | Dietitian group, Doctor group |
Primary outcome
IBS-SSS
Time frame: From enrollment to the end of treatment at 8 weeks
Irritable Bowel Syndrome Symptom Severity Score (IBS-SSS). The IBS-SSS consists of 5 questions, each scored from 0 to 100, with a maximum possible total score of 500. It determines the severity of abdominal pain, abdominal pain frequency, abdominal bloating severity, satisfaction with bowel habits, and the impact of the disease on quality of life. Total scores are classified as follows: 75-174 points = mild IBS, 175-299 points = moderate IBS, and greater than or equal to 300 points = severe IBS. Higher scores indicate more severe IBS symptoms.
GSRS
Time frame: From enrollment to the end of treatment at 8 weeks
Gastrointestinal Symptom Rating Scale (GSRS). The GSRS is a 15-item questionnaire that uses a 5-point Likert scale to assess the severity of gastrointestinal symptoms across 5 subscales: abdominal pain, reflux, diarrhoea, indigestion, and constipation. Scores are aggregated to determine symptom severity, where higher scores represent a higher severity of gastrointestinal symptoms.
Fecal Calprotectin
Time frame: From enrollment to the end of treatment at 8 weeks
Fecal calprotectin levels will be analyzed from stool samples collected from participants to evaluate gastrointestinal inflammation.
Hs-CRP
Time frame: From enrollment to the end of treatment at 8 weeks
High-Sensitivity C-Reactive Protein (hs-CRP). Hs-CRP levels will be analyzed from blood samples collected from individuals to monitor systemic biochemical findings of inflammation.
5 secondary outcomes
Anthropometric measurement data
Time frame: From enrollment to the end of treatment at 8 weeks
IPAQ-SF
Time frame: From enrollment to the end of treatment at 8 weeks
Epworth Sleepiness Scale (ESS)
Time frame: From enrollment to the end of treatment at 8 weeks
Data Collection Form
Time frame: At the beginning of the study
Daily Total FODMAP Intake
Time frame: From enrollment to the end of treatment at 8 weeks
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 2 Jun 2026.
- Individual participant dataSharing planned: No
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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.
Sevde KAHRAMAN, Asst. Prof. study chair
Biruni University
Zeynep Çavdar, Master's student and dietitan study director
Biruni University
Koray Koçhan, Specialist of Gastroenterology principal investigator
Department of Gastroenterology, Biruni University Faculty of Medicine Hospital
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Low-FODMAP Diet Intervention in people with Irritable Bowel Syndrome (IBS), run by Biruni University at 2 sites in Turkey (Türkiye).
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 2 inclusion and 3 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 2 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in Turkey (Türkiye). 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?
IBS-SSS (time frame: From enrollment to the end of treatment at 8 weeks). The study lists 4 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 2 Jun 2026.