Morbid ObesityChronoNutrNCT07303036
Chronobiological Determinants of Gut Microbiome
An observational study of Morbid Obesity, run by Hacettepe University at 1 site in Turkey (Türkiye).
Trial summary
The aim of this study is to examine how the number of daily eating occasions and the timing of energy intake influence gut microbiome composition in both morbidly obese and non-obese individuals. The analysis is based on baseline data from a case-control study involving 11 non-obese and 23 morbidly obese adults. Read more about this study
- Who is it for?
- Ages 26 to 60 yearsHealthy volunteers can take part
- Conditions the study is for
- Morbid Obesity
- How many people
- 34 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 20 Oct 2016to 21 Jun 2019
- Phase
- Observational
- 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 26 to 60 years
- All sexes
- Healthy volunteers accepted
- Adult
Study population: Study Population: Participants were recruited into three groups: Case group: 23 morbidly obese participants Control group: 11 non-obese participants, including lean (n=5) and pre-obese (n=6)
Who may be able to join
- Adults aged 19 to 65 years Morbid obesity (case group) Non-obese status, including lean or pre-obese (control group) Willingness to participate in the study Ability to provide informed consent
Who cannot join
- Age < 26 years or > 60 years Presence of acute or chronic inflammatory diseases Diagnosis of infectious diseases History of cancer Alcohol addiction Use of antibiotics within 3 months prior to screening
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Chronobiological Determinants of Gut Microbiome: The Effects of Meal Timing and Eating Frequency
The aim of this study is to examine how the number of daily eating occasions and the timing of energy intake influence gut microbiome composition in both morbidly obese and non-obese individuals. The analysis is based on baseline data from a case-control study involving 11 non-obese and 23 morbidly obese adults. Participants were excluded if they were younger than 19 or older than 65 years, had an acute or chronic inflammatory condition, had been diagnosed with an infectious disease, cancer, or alcohol dependence, or had used antibiotics within the three months prior to screening.
Read the detailed description
This study aimed to investigate how the number of daily eating occasions and the timing of energy intake influence gut microbiome composition in morbidly obese and non-obese adults. This case-control study examined the gut microbiota of 23 morbidly obese individuals (BMI > 40 kg/m²) and 11 non-obese individuals (BMI < 30 kg/m²).
Dietary intake was assessed using 24-hour dietary recall records. From these data, the number of meals, total daily energy intake, and the proportion of energy consumed within specific time intervals (06:00-13:00, 13:00-20:00, and 20:00-06:00) were calculated. Energy intake occurring after 20:00 was defined as nighttime eating.
Participant eligibility required individuals to be between 19 and 65 years of age, free from acute or chronic inflammatory diseases, and without diagnoses of infectious diseases, cancer, or alcohol addiction. Additionally, participants were excluded if they had taken antibiotics within the three months preceding the screening.
- Conditions
- Morbid Obesity
- Keywords
- morbid obesity, chrononutrition, dietary intake
- Medical subject headings
- Obesity, Morbid
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Morbidly obese | People who are classified as morbidly obese (BMI>40 kg/m2) | |
| Non-obese | People who are classified as non-obese (BMI<30 kg/m2) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Gut microbial profiles of participants
Gut microbial profiles of participants at phylum and sub-phylum levels
Measured: Baseline
Meal frequency of participants
Number of meals consumed per day
Measured: Baseline
Total daily energy intake
Total daily energy intake assessed from dietary data (kcal/day)
Measured: Baseline
Distribution of energy intake by time of day
Percentage of total daily energy intake consumed during predefined time periods of the day (e.g., morning, afternoon, evening, night)
Measured: Baseline
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted24 Dec 2025
- Study start20 Oct 2016
- Primary completion1 Jan 2018
- Study completion21 Jun 2019
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Morbid ObesityStudies of the same condition, open and under way.
- More trials run by Hacettepe 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
- Observational
- Observational model
- Case-control
- Time perspective
- Cross-sectional
- Enrolment
- 34 participants (actual)
Sponsor and investigators
- Lead sponsor
- Hacettepe University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Aslihan Ozdemir, Hacettepe University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07303036
- Sponsor's protocol ID
- GO 23/450
- Acronym
- ChronoNutr
- Status last verified
- Dec 2025
- First submitted
- 3 Dec 2025
- Last updated
- 24 Dec 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Individual participant data will not be shared because the study does not include a data-sharing plan.
Study at a glance
From the registry record, last updated by the sponsor on 24 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Chronobiological Determinants of Gut Microbiome: The Effects of Meal Timing and Eating Frequency
- ClinicalTrials.gov ID
- NCT07303036
- Acronym / sponsor ID
- ChronoNutr / GO 23/450
- Conditions
- Morbid Obesity
- Keywords
- morbid obesity, chrononutrition, dietary intake
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 34 participants (actual)
- Lead sponsor
- Hacettepe UniversityUniversity, hospital or other
- Study start
- 20 Oct 2016 (actual)
- Primary completion
- 1 Jan 2018 (actual)
- Study completion
- 21 Jun 2019 (actual)
- First posted
- 24 Dec 2025 (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.
The aim of this study is to examine how the number of daily eating occasions and the timing of energy intake influence gut microbiome composition in both morbidly obese and non-obese individuals. The analysis is based on baseline data from a case-control study involving 11 non-obese and 23 morbidly obese adults. Participants were excluded if they were younger than 19 or older than 65 years, had an acute or chronic inflammatory condition, had been diagnosed with an infectious disease, cancer, or alcohol dependence, or had used antibiotics within the three months prior to screening.
Detailed description
This study aimed to investigate how the number of daily eating occasions and the timing of energy intake influence gut microbiome composition in morbidly obese and non-obese adults. This case-control study examined the gut microbiota of 23 morbidly obese individuals (BMI > 40 kg/m²) and 11 non-obese individuals (BMI < 30 kg/m²).
Dietary intake was assessed using 24-hour dietary recall records. From these data, the number of meals, total daily energy intake, and the proportion of energy consumed within specific time intervals (06:00-13:00, 13:00-20:00, and 20:00-06:00) were calculated. Energy intake occurring after 20:00 was defined as nighttime eating.
Participant eligibility required individuals to be between 19 and 65 years of age, free from acute or chronic inflammatory diseases, and without diagnoses of infectious diseases, cancer, or alcohol addiction. Additionally, participants were excluded if they had taken antibiotics within the three months preceding the screening.
Study design
- Observational model
- Case-control
- Time perspective
- Cross-sectional
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Morbidly obese | – | –People who are classified as morbidly obese (BMI>40 kg/m2) |
| Non-obese | – | –People who are classified as non-obese (BMI<30 kg/m2) |
Who may qualify
- Ages
- 26 to 60 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
- Study population
- Study Population: Participants were recruited into three groups: Case group: 23 morbidly obese participants Control group: 11 non-obese participants, including lean (n=5) and pre-obese (n=6)
Key inclusion criteria (1 listed)
- Adults aged 19 to 65 years Morbid obesity (case group) Non-obese status, including lean or pre-obese (control group) Willingness to participate in the study Ability to provide informed consent
Key exclusion criteria (1 listed)
- Age < 26 years or > 60 years Presence of acute or chronic inflammatory diseases Diagnosis of infectious diseases History of cancer Alcohol addiction Use of antibiotics within 3 months prior to screening
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Gut microbial profiles of participants
Time frame: Baseline
Gut microbial profiles of participants at phylum and sub-phylum levels
Meal frequency of participants
Time frame: Baseline
Number of meals consumed per day
Total daily energy intake
Time frame: Baseline
Total daily energy intake assessed from dietary data (kcal/day)
Distribution of energy intake by time of day
Time frame: Baseline
Percentage of total daily energy intake consumed during predefined time periods of the day (e.g., morning, afternoon, evening, night)
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 24 Dec 2025.
- Individual participant dataSharing planned: No. Individual participant data will not be shared because the study does not include a data-sharing plan.
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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.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Morbid Obesity, run by Hacettepe University at 1 site 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 1 inclusion and 1 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 24 Dec 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 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?
Gut microbial profiles of participants (time frame: Baseline). 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 24 Dec 2025.