Microbial ColonizationNCT05748080
The Apple Study: Two Apples a Day, Keep the Doctor Away?
A study testing Eating apples in people with Microbial Colonization and Enzyme Overdose, run by Maastricht University Medical Center.
Trial summary
The goal of this clinical trial is to learn about the gut microbiome in healthy postmenopausal women aged 50-64. The main questions it aims to answer are: Investigate whether the activity of the bacterial enzyme β-glucuronidase and the abundance of β-glucuronidase-producing bacteria could be decreased by ingestion of… Read more about this study
- Who is it for?
- Ages 50 to 64 years, women onlyHealthy volunteers can take part
- Conditions the study is for
- Microbial Colonization, Enzyme Overdose
- What is being tested?
- Eating apples
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 12 participants
- Where
- No sites listed yet
- Study dates
- 1 Mar 2023to 31 Oct 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 50 to 64 years
- Women only
- Healthy volunteers accepted
- Adult
Who may be able to join
- Age 50-64
- Postmenopausal women
- Recent negative breast cancer screening (< 6 months)
Who cannot join
- The regular consumption of one ore more apples a day
- Previous gastrointestinal surgery (excl. appendix surgery)
- Any type of cancer in history, except for basal cell carcinoma (BCC)
- Inflammatory bowel disease
- Mammography older than 6 months
- Antibiotic use within three months before fecal sampling
Show all 9Show fewer
- Physically or mentally incapable or incompetent to sign informed consent
- Known apple allergy or complaints matching with apple allergy
- Less good dental state
Trial locations and contacts
No sites are listed yet.
About this study
Official title: Two Apples a Day, Keep the Doctor Away?
The goal of this clinical trial is to learn about the gut microbiome in healthy postmenopausal women aged 50-64. The main questions it aims to answer are:
- Investigate whether the activity of the bacterial enzyme β-glucuronidase and the abundance of β-glucuronidase-producing bacteria could be decreased by ingestion of 2 apples a day for a period of 6 weeks
- Examine changes in gut microbiota composition, diversity, and functional capacity
- Examine feasibility of eating 2 apples a day for a period of 6 weeks
Participants will eat 2 apples a day for a period of 6 weeks.
Six weeks includes the period from the start of the study and gathering of baseline characteristics/questionnaires till the finish.
Read the detailed description
It is know that estrogen levels decrease after menopause. There are many different factors affecting these levels though; the gut microbiome has been identified as one of these. Not only the composition of the gut microbiota plays a role here, but also its activity is of special interest. The gut microbiota for instance produces the bacterial enzyme β-glucuronidase which has been shown to de-conjugate biliary excreted estrogens, leading to reactivation and reabsorption of estrogens into the bloodstream. It might be expected that this reabsorption results in elevated blood estrogen levels. Elevated levels of estrogen have been linked to not only development but also recurrence of breast cancer.
Apples are known for their pectin which has prebiotic properties and a potential decreasing effect on β-glucuronidase activity. In vitro studies and animal studies have already shown the β-glucuronidase decreasing impact of pectin. In humans this was never examined before.
This study aims to investigate whether it is possible to lower the activity of the bacterial enzyme β-glucuronidase and the abundance of β-glucuronidase-producing bacteria by a simple dietary intervention. This dietary intervention consists of the ingestion of two whole apples a day, one in the morning and one in the evening, during the period of 6 weeks. Thereby this study aims to examine the feasibility of this intervention.
It is hypothesized that
- this is a feasible intervention
- this results in a decrease in the activity of the bacterial enzyme β-glucuronidase and the abundance of β-glucuronidase-producing bacteria. Which would be in line with the findings of in vitro and animal studies and
- an increase in microbial diversity
- Conditions
- Microbial Colonization, Enzyme Overdose
- Being tested
- Eating apples
- Medical subject headings
- Communicable Diseases
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Eating applesOther
the eating of 2 apples a day for a period of 6 weeks
| Study group | Role | What they receive |
|---|---|---|
| Apple intervention | Experimental | the eating of 2 apples a day for a period of 6 weeks Receives: Other: Eating apples |
What is being measured
The primary outcome is the main question the study is designed to answer.
The activity of the bacterial enzyme β-glucuronidase and the abundance of β-glucuronidase-producing bacteria
This will be measured in fecal samples by using a validated β-glucuronidase enzyme activity assay, which is based on previous studies.
Measured: 6 weeks per patient
Changes in gut microbiota composition, diversity, and functional capacity
Gut microbiota composition, diversity
Measured: 6 weeks per patient
Feasibility of eating 2 apples a day for a period of 6 weeks
feasibility
Measured: 6 weeks per patient
Secondary outcomes (2)
Fecal levels of short-chain fatty acids (SCFA)
SCFA
Measured: 6 weeks per patient
Dietary intake, medication, stool classification and frequency, blood pressure, weight, length and quality of life before and after the intervention
diet/medication etc
Measured: 6 weeks per patient
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted28 Feb 2023
- Study start1 Mar 2023 (estimated)
- Primary completion30 Apr 2023 (estimated)
- Study completion31 Oct 2024 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Microbial ColonizationStudies 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
- 12 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Maastricht University Medical Center
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Marjolein Smidt, prof. dr., Principal investigator, Maastricht University Medical Center
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05748080
- Sponsor's protocol ID
- METC22-064
- Status last verified
- Feb 2023
- First submitted
- 30 Jan 2023
- Last updated
- 28 Feb 2023
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 28 Feb 2023. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Two Apples a Day, Keep the Doctor Away?
- ClinicalTrials.gov ID
- NCT05748080
- Acronym / sponsor ID
- METC22-064
- Conditions
- Microbial Colonization, Enzyme Overdose
- Study type
- Interventional
- Recruitment status
- Unknown status
- Enrolment
- 12 participants (estimated)
- Lead sponsor
- Maastricht University Medical CenterUniversity, hospital or other
- Study start
- 1 Mar 2023 (estimated)
- Primary completion
- 30 Apr 2023 (estimated)
- Study completion
- 31 Oct 2024 (estimated)
- First posted
- 28 Feb 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.
The goal of this clinical trial is to learn about the gut microbiome in healthy postmenopausal women aged 50-64. The main questions it aims to answer are:
- Investigate whether the activity of the bacterial enzyme β-glucuronidase and the abundance of β-glucuronidase-producing bacteria could be decreased by ingestion of 2 apples a day for a period of 6 weeks
- Examine changes in gut microbiota composition, diversity, and functional capacity
- Examine feasibility of eating 2 apples a day for a period of 6 weeks
Participants will eat 2 apples a day for a period of 6 weeks.
Six weeks includes the period from the start of the study and gathering of baseline characteristics/questionnaires till the finish.
Detailed description
It is know that estrogen levels decrease after menopause. There are many different factors affecting these levels though; the gut microbiome has been identified as one of these. Not only the composition of the gut microbiota plays a role here, but also its activity is of special interest. The gut microbiota for instance produces the bacterial enzyme β-glucuronidase which has been shown to de-conjugate biliary excreted estrogens, leading to reactivation and reabsorption of estrogens into the bloodstream. It might be expected that this reabsorption results in elevated blood estrogen levels. Elevated levels of estrogen have been linked to not only development but also recurrence of breast cancer.
Apples are known for their pectin which has prebiotic properties and a potential decreasing effect on β-glucuronidase activity. In vitro studies and animal studies have already shown the β-glucuronidase decreasing impact of pectin. In humans this was never examined before.
This study aims to investigate whether it is possible to lower the activity of the bacterial enzyme β-glucuronidase and the abundance of β-glucuronidase-producing bacteria by a simple dietary intervention. This dietary intervention consists of the ingestion of two whole apples a day, one in the morning and one in the evening, during the period of 6 weeks. Thereby this study aims to examine the feasibility of this intervention.
It is hypothesized that
- this is a feasible intervention
- this results in a decrease in the activity of the bacterial enzyme β-glucuronidase and the abundance of β-glucuronidase-producing bacteria. Which would be in line with the findings of in vitro and animal studies and
- an increase in microbial diversity
Study design
- Primary purpose
- Other
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Apple intervention | Experimental | Other: Eating applesthe eating of 2 apples a day for a period of 6 weeks |
Who may qualify
- Ages
- 50 to 64 years
- Sex
- Female only
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (3 listed)
- Age 50-64
- Postmenopausal women
- Recent negative breast cancer screening (< 6 months)
Key exclusion criteria (9 listed)
- The regular consumption of one ore more apples a day
- Previous gastrointestinal surgery (excl. appendix surgery)
- Any type of cancer in history, except for basal cell carcinoma (BCC)
- Inflammatory bowel disease
- Mammography older than 6 months
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 |
|---|---|---|
| Eating applesthe eating of 2 apples a day for a period of 6 weeks | Other | Apple intervention |
Primary outcome
The activity of the bacterial enzyme β-glucuronidase and the abundance of β-glucuronidase-producing bacteria
Time frame: 6 weeks per patient
This will be measured in fecal samples by using a validated β-glucuronidase enzyme activity assay, which is based on previous studies.
Changes in gut microbiota composition, diversity, and functional capacity
Time frame: 6 weeks per patient
Gut microbiota composition, diversity
Feasibility of eating 2 apples a day for a period of 6 weeks
Time frame: 6 weeks per patient
feasibility
2 secondary outcomes
Fecal levels of short-chain fatty acids (SCFA)
Time frame: 6 weeks per patient
Dietary intake, medication, stool classification and frequency, blood pressure, weight, length and quality of life before and after the intervention
Time frame: 6 weeks per patient
Results and safety
Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 28 Feb 2023.
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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.
Marjolein Smidt, prof. dr. principal investigator
Maastricht University Medical Center
Questions about this trial
What is this clinical trial studying?
A study testing Eating apples in people with Microbial Colonization and Enzyme Overdose, run by Maastricht University Medical Center.
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 9 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: status not confirmed, as of the sponsor's last update on 28 Feb 2023. Status can change between updates, so confirm with the study contact before making plans.
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?
Results are not available in the source record.
How can a doctor refer a patient or contact the research team?
Contact Marjolein Smidt, prof. dr. (043 - 3877477, m.smidt@mumc.nl), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
The activity of the bacterial enzyme β-glucuronidase and the abundance of β-glucuronidase-producing bacteria (time frame: 6 weeks per patient). The study lists 3 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 28 Feb 2023.