Irritable Bowel SyndromeNCT05978973
Elemental Diet and Gut Microbiome
A study testing Elemental Diet in people with Irritable Bowel Syndrome, run by Cedars-Sinai Medical Center at 1 site in United States.
Trial summary
he primary objective of this study is to assess changes in stool microbiome profiles in patients after an elemental diet. Read more about this study
- Who is it for?
- Ages 18 to 85 years
- Conditions the study is for
- Irritable Bowel Syndrome
- What is being tested?
- Elemental Diet
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 30 participants
- Where
- 1 siteUnited States
- Study dates
- 6 Aug 2023to 14 Dec 2023
- 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 85 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- • Participant must be able to understand and provide informed consent
- Males and Females ≥18-85
- Female subjects of childbearing potential must have a negative pregnancy test upon study entry
- Female (and male) subjects with reproductive potential, must agree to use FDA approved methods of birth control for the duration of the study
- Subject self-reports experiencing SIBO symptoms within 30 days
- Positive (abnormal) lactulose breath test for SIBO on visit 1 (day -7) as defined as:
- Rise of hydrogen ≥ 20ppm within 90 minutes on LBT OR
- A methane level ≥10 ppm at any point during the 120-minute LBT
Who cannot join
- • Inability or unwillingness of a participant to give written informed consent or comply with study protocol
- Pregnancy or lactating
- Type 1 or type 2 diabetes
- Active or ongoing infection that requires antibiotics other than the participants known prophylactic medications (i.e. active infection or antibiotic use in the last 1 month)
- Any condition that, in the opinion of the investigator, contraindicates participation in this study will be excluded from study participation.
- History of known Phenylketonuria (PKU) disease
- Non-English-speaking participants
Trial locations and contacts
1 site in 1 country.
United States1 site
Cedars-Sinai Medical Center
Los Angeles, California, 90048
About this study
he primary objective of this study is to assess changes in stool microbiome profiles in patients after an elemental diet.
Read the detailed description
The gut microbiome is the collection of microbes residing inside the gastrointestinal (GI) tract. The involvement of the gut microbiome has been demonstrated in multiple diseases processes including irritable bowel syndrome, small intestinal bacterial overgrowth (SIBO), Crohn's disease, and ulcerative colitis among many other diseases. A "healthy" diverse gut microbiome is associated with a better response to infections and immunopathogenic insults.
Many factors can affect the gut microbiome including medications, age, disease states and diet. Among these factors, diet is the easiest factor that can be modified to improve the gut microbiome. However, conducting dietary trials is challenging due to the inability to fully standardize what subjects eat even with strict dietary instructions. Moreover, individual preferences/allergies, the source of dietary ingredients, freshness, and food preparation are important steps which affect the diet and are challenging to standardize among subjects in a diet trial. This has led to significant ambiguity regarding the true extent and depth of dietary modifications on gut microbiome.
Apart from vitamins and micronutrients, the three main food macronutrients in the human diet are carbohydrates, protein and fat. Upon digestion, carbohydrates are broken into monosaccharides, proteins into amino acids and fats mainly into fatty acids. Elemental diets contain all daily required vitamins, micronutrients and macronutrients. The ingredients are readily digestible (carbohydrates, amino acids and medium chain fatty acids) and are absorbed within the proximal small bowel. One main disadvantage of elemental diets such as Vivonex is their unpalatability which has limited their use. A palatable elemental diet can be a very valuable tool to enable us to assess the effects of diet on the gut microbiome as it bypasses several confounding effects in dietary trials such as food allergies, individual digestion variability, completeness of the diet ingredients, and food preparation.
SIBO is a condition in which the gut microbiome plays an integral role and is defined by abnormal and excessive numbers of bacteria in the small bowel.4 Interest in SIBO has been fueled by the ever-increasing awareness of the human microbiome and its potential relationships to human health and disease. SIBO is a preferred condition to assess the effects of elemental diet on the gut microbiome, given the known role of the gut microbiome in SIBO. Those with SIBO experience a range of intestinal and extraintestinal symptoms including diarrhea, nausea, bloating, abdominal pain, and excess gas.
Commonly, SIBO has been defined by two methods: direct culture of small bowel aspirates, and indirect assessment using carbohydrate (e.g. lactulose or glucose) breath testing. SIBO is generally treated with antibiotics. Low fermentable and elemental diets also have positive effects in SIBO. Based on the potential effects of diet on the gut microbiome, we hypothesize that a two-week period of an elemental diet can change the gut microbiome in SIBO subjects.
- Conditions
- Irritable Bowel Syndrome
- Being tested
- Elemental 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.
Elemental DietDietary supplement
. Elemental diets contain all daily required vitamins, micronutrients and macronutrients. The ingredients are readily digestible (carbohydrates, amino acids and medium chain fatty acids) and are absorbed within the proximal small bowel. One main disadvantage of elemental diets such as Vivonex is their unpalatability3 which has limited their use.
| Study group | Role | What they receive |
|---|---|---|
| elemental diet | Experimental | subjects will be using the elemental diet packets daily. Subjects who are positive for excessive methane (i.e. methane level>10 ppm) will be required to complete a single daily fasting methane measurement (SMM) for the duration of the 14 days. Receives: Dietary Supplement: Elemental Diet |
What is being measured
The primary outcome is the main question the study is designed to answer.
assess changes in stool microbiome profiles
is to assess changes in stool microbiome profiles in patients after an elemental diet, as determined by 16S rRNA gene sequencing • Microbiome profiles will be determined in stool samples provided on visit 2 (day 0), visit 4 (day 14) and visit 6 (day 28). These analyses will be performed in batch at the end of the study and the profiles at visit 4 (day 14) and visit 6 (day 28) will be compared to those at visit 2 (day 0).
Measured: 28 DAYS
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted7 Aug 2023
- Study start6 Aug 2023
- Primary completion14 Dec 2023
- Study completion14 Dec 2023
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (10)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
- Other
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 30 participants (actual)
Sponsor and investigators
- Lead sponsor
- Cedars-Sinai Medical Center
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Bianca Chang, Cedars-Sinai Medical Center
- Investigators
- Bianca Chang, MD, Principal investigator, Cedars-Sinai Medical Center
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05978973
- Sponsor's protocol ID
- STUDY00002455:
- Status last verified
- Jan 2024
- First submitted
- 30 Jul 2023
- Last updated
- 23 Jan 2024
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Pimentel M, Mathur R, Wang J, Chang C, Hosseini A, Fiorentino A, Rashid M, Pichetshote N, Basseri B, Treyzon L, Chang B, Leite G, Morales W, Weitsman S, Kraus A, Rezaie A. A Smartphone Application Using Artificial Intelligence Is Superior To Subject Self-Reporting When Assessing Stool Form. Am J Gastroenterol. 2022 Jul 1;117(7):1118-1124. doi: 10.14309/ajg.0000000000001723. Epub 2022 Mar 14.
PubMed 35288511Wu X, Zhu Y, Yang M, Zhang J, Lin D. Biological responses of Eisenia fetida towards the exposure and metabolism of tris (2-butoxyethyl) phosphate. Sci Total Environ. 2022 Mar 10;811:152285. doi: 10.1016/j.scitotenv.2021.152285. Epub 2021 Dec 18.
PubMed 34933047Moore DA, Schatz D. Overprecision increases subsequent surprise. PLoS One. 2020 Jul 8;15(7):e0227084. doi: 10.1371/journal.pone.0227084. eCollection 2020.
PubMed 32639957Kilic E, Tennstedt P, Hogner A, Lebok P, Sauter G, Bokemeyer C, Izbicki JR, Wilczak W. The zinc-finger transcription factor SALL4 is frequently expressed in human cancers: association with clinical outcome in squamous cell carcinoma but not in adenocarcinoma of the esophagus. Virchows Arch. 2016 Apr;468(4):483-92. doi: 10.1007/s00428-016-1908-y. Epub 2016 Jan 27.
PubMed 26818834Rubin R. Botulinum Toxin to Treat Endometriosis Pain. JAMA. 2019 Aug 27;322(8):716. doi: 10.1001/jama.2019.12350. No abstract available.
PubMed 31454029Rotovnik Kozjek N, Kompan L, Zagar T, Mrevlje Z. Influence of enteral glutamine on inflammatory and hormonal response in patients with rectal cancer during preoperative radiochemotherapy. Eur J Clin Nutr. 2017 May;71(5):671-673. doi: 10.1038/ejcn.2017.11. Epub 2017 Mar 8.
PubMed 28272402Pimentel M, Constantino T, Kong Y, Bajwa M, Rezaei A, Park S. A 14-day elemental diet is highly effective in normalizing the lactulose breath test. Dig Dis Sci. 2004 Jan;49(1):73-7. doi: 10.1023/b:ddas.0000011605.43979.e1.
PubMed 14992438Gombert A, Van Herzeele I. We Want to OPERATE! Eur J Vasc Endovasc Surg. 2020 May;59(5):775. doi: 10.1016/j.ejvs.2020.01.033. Epub 2020 Feb 20. No abstract available.
PubMed 32088068Speller B, Metcalfe K, Kennedy ED, Facey M, Greenblatt E, Scheer AS, Warner E, Joy AA, Wright FC, Baxter NN. The "Begin Exploring Fertility Options, Risks and Expectations" (BEFORE) decision aid: development and alpha testing of a fertility tool for premenopausal breast cancer patients. BMC Med Inform Decis Mak. 2019 Oct 28;19(1):203. doi: 10.1186/s12911-019-0912-y.
PubMed 31660965Rezaie A, Chang BW, de Freitas Germano J, Leite G, Mathur R, Houser K, Hosseini A, Brimberry D, Rashid M, Mehravar S, Villanueva-Millan MJ, Sanchez M, Weitsman S, Fajardo CM, Rivera IG, Joo L, Chan Y, Barlow GM, Pimentel M. Effect, Tolerability, and Safety of Exclusive Palatable Elemental Diet in Patients With Intestinal Microbial Overgrowth. Clin Gastroenterol Hepatol. 2025 Nov;23(12):2306-2317.e7. doi: 10.1016/j.cgh.2025.03.002. Epub 2025 Apr 4.
PubMed 40189034
Study at a glance
From the registry record, last updated by the sponsor on 23 Jan 2024. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Elemental Diet and Gut Microbiome
- ClinicalTrials.gov ID
- NCT05978973
- Acronym / sponsor ID
- STUDY00002455:
- Conditions
- Irritable Bowel Syndrome
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 30 participants (actual)
- Lead sponsor
- Cedars-Sinai Medical CenterUniversity, hospital or other
- Study start
- 6 Aug 2023 (actual)
- Primary completion
- 14 Dec 2023 (actual)
- Study completion
- 14 Dec 2023 (actual)
- First posted
- 7 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.
he primary objective of this study is to assess changes in stool microbiome profiles in patients after an elemental diet.
Detailed description
The gut microbiome is the collection of microbes residing inside the gastrointestinal (GI) tract. The involvement of the gut microbiome has been demonstrated in multiple diseases processes including irritable bowel syndrome, small intestinal bacterial overgrowth (SIBO), Crohn's disease, and ulcerative colitis among many other diseases. A "healthy" diverse gut microbiome is associated with a better response to infections and immunopathogenic insults.
Many factors can affect the gut microbiome including medications, age, disease states and diet. Among these factors, diet is the easiest factor that can be modified to improve the gut microbiome. However, conducting dietary trials is challenging due to the inability to fully standardize what subjects eat even with strict dietary instructions. Moreover, individual preferences/allergies, the source of dietary ingredients, freshness, and food preparation are important steps which affect the diet and are challenging to standardize among subjects in a diet trial. This has led to significant ambiguity regarding the true extent and depth of dietary modifications on gut microbiome.
Apart from vitamins and micronutrients, the three main food macronutrients in the human diet are carbohydrates, protein and fat. Upon digestion, carbohydrates are broken into monosaccharides, proteins into amino acids and fats mainly into fatty acids. Elemental diets contain all daily required vitamins, micronutrients and macronutrients. The ingredients are readily digestible (carbohydrates, amino acids and medium chain fatty acids) and are absorbed within the proximal small bowel. One main disadvantage of elemental diets such as Vivonex is their unpalatability which has limited their use. A palatable elemental diet can be a very valuable tool to enable us to assess the effects of diet on the gut microbiome as it bypasses several confounding effects in dietary trials such as food allergies, individual digestion variability, completeness of the diet ingredients, and food preparation.
SIBO is a condition in which the gut microbiome plays an integral role and is defined by abnormal and excessive numbers of bacteria in the small bowel.4 Interest in SIBO has been fueled by the ever-increasing awareness of the human microbiome and its potential relationships to human health and disease. SIBO is a preferred condition to assess the effects of elemental diet on the gut microbiome, given the known role of the gut microbiome in SIBO. Those with SIBO experience a range of intestinal and extraintestinal symptoms including diarrhea, nausea, bloating, abdominal pain, and excess gas.
Commonly, SIBO has been defined by two methods: direct culture of small bowel aspirates, and indirect assessment using carbohydrate (e.g. lactulose or glucose) breath testing. SIBO is generally treated with antibiotics. Low fermentable and elemental diets also have positive effects in SIBO. Based on the potential effects of diet on the gut microbiome, we hypothesize that a two-week period of an elemental diet can change the gut microbiome in SIBO subjects.
Study design
- Primary purpose
- Other
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| elemental diet | Experimental | Dietary Supplement: Elemental Dietsubjects will be using the elemental diet packets daily. Subjects who are positive for excessive methane (i.e. methane level>10 ppm) will be required to complete a single daily fasting methane measurement (SMM) for the duration of the 14 days. |
Who may qualify
- Ages
- 18 to 85 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (8 listed)
- • Participant must be able to understand and provide informed consent
Key exclusion criteria (7 listed)
- • Inability or unwillingness of a participant to give written informed consent or comply with study protocol
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 |
|---|---|---|
| Elemental Diet. Elemental diets contain all daily required vitamins, micronutrients and macronutrients. The ingredients are readily digestible (carbohydrates, amino acids and medium chain fatty acids) and are absorbed within the proximal small bowel. One main disadvantage of elemental diets such as Vivonex is their unpalatability3 which has limited their use. | Dietary supplement | elemental diet |
Primary outcome
assess changes in stool microbiome profiles
Time frame: 28 DAYS
is to assess changes in stool microbiome profiles in patients after an elemental diet, as determined by 16S rRNA gene sequencing • Microbiome profiles will be determined in stool samples provided on visit 2 (day 0), visit 4 (day 14) and visit 6 (day 28). These analyses will be performed in batch at the end of the study and the profiles at visit 4 (day 14) and visit 6 (day 28) will be compared to those at visit 2 (day 0).
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 23 Jan 2024.
- Background: PubMed 35288511Pimentel M, Mathur R, Wang J, Chang C, Hosseini A, Fiorentino A, Rashid M, Pichetshote N, Basseri B, Treyzon L, Chang B, Leite G, Morales W, Weitsman S, Kraus A, Rezaie A. A Smartphone Application Using Artificial Intelligence Is Superior To Subject Self-Reporting When Assessing Stool Form. Am J Gastroenterol. 2022 Jul 1;117(7):1118-1124. doi: 10.14309/ajg.0000000000001723. Epub 2022 Mar 14.
- Background: PubMed 34933047Wu X, Zhu Y, Yang M, Zhang J, Lin D. Biological responses of Eisenia fetida towards the exposure and metabolism of tris (2-butoxyethyl) phosphate. Sci Total Environ. 2022 Mar 10;811:152285. doi: 10.1016/j.scitotenv.2021.152285. Epub 2021 Dec 18.
- Background: PubMed 32639957Moore DA, Schatz D. Overprecision increases subsequent surprise. PLoS One. 2020 Jul 8;15(7):e0227084. doi: 10.1371/journal.pone.0227084. eCollection 2020.
- Background: PubMed 26818834Kilic E, Tennstedt P, Hogner A, Lebok P, Sauter G, Bokemeyer C, Izbicki JR, Wilczak W. The zinc-finger transcription factor SALL4 is frequently expressed in human cancers: association with clinical outcome in squamous cell carcinoma but not in adenocarcinoma of the esophagus. Virchows Arch. 2016 Apr;468(4):483-92. doi: 10.1007/s00428-016-1908-y. Epub 2016 Jan 27.
- Background: PubMed 31454029Rubin R. Botulinum Toxin to Treat Endometriosis Pain. JAMA. 2019 Aug 27;322(8):716. doi: 10.1001/jama.2019.12350. No abstract available.
- Background: PubMed 28272402Rotovnik Kozjek N, Kompan L, Zagar T, Mrevlje Z. Influence of enteral glutamine on inflammatory and hormonal response in patients with rectal cancer during preoperative radiochemotherapy. Eur J Clin Nutr. 2017 May;71(5):671-673. doi: 10.1038/ejcn.2017.11. Epub 2017 Mar 8.
- Background: PubMed 14992438Pimentel M, Constantino T, Kong Y, Bajwa M, Rezaei A, Park S. A 14-day elemental diet is highly effective in normalizing the lactulose breath test. Dig Dis Sci. 2004 Jan;49(1):73-7. doi: 10.1023/b:ddas.0000011605.43979.e1.
- Background: PubMed 32088068Gombert A, Van Herzeele I. We Want to OPERATE! Eur J Vasc Endovasc Surg. 2020 May;59(5):775. doi: 10.1016/j.ejvs.2020.01.033. Epub 2020 Feb 20. No abstract available.
- Background: PubMed 31660965Speller B, Metcalfe K, Kennedy ED, Facey M, Greenblatt E, Scheer AS, Warner E, Joy AA, Wright FC, Baxter NN. The "Begin Exploring Fertility Options, Risks and Expectations" (BEFORE) decision aid: development and alpha testing of a fertility tool for premenopausal breast cancer patients. BMC Med Inform Decis Mak. 2019 Oct 28;19(1):203. doi: 10.1186/s12911-019-0912-y.
- Derived from this study: PubMed 40189034Rezaie A, Chang BW, de Freitas Germano J, Leite G, Mathur R, Houser K, Hosseini A, Brimberry D, Rashid M, Mehravar S, Villanueva-Millan MJ, Sanchez M, Weitsman S, Fajardo CM, Rivera IG, Joo L, Chan Y, Barlow GM, Pimentel M. Effect, Tolerability, and Safety of Exclusive Palatable Elemental Diet in Patients With Intestinal Microbial Overgrowth. Clin Gastroenterol Hepatol. 2025 Nov;23(12):2306-2317.e7. doi: 10.1016/j.cgh.2025.03.002. Epub 2025 Apr 4.
- 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.
Bianca Chang, MD principal investigator
Cedars-Sinai Medical Center
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Elemental Diet in people with Irritable Bowel Syndrome, run by Cedars-Sinai Medical Center at 1 site in United States.
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 8 inclusion and 7 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 23 Jan 2024. 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 States. 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?
assess changes in stool microbiome profiles (time frame: 28 DAYS). 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 NCT05978973, which also lists 10 linked publications.
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 23 Jan 2024.