Focus of Study: 1- Effect of Tea Consumption on Gut MicrobiotaNCT05019573
Can the Reduction of Iron Availability Caused by Tea Consumption Change the Gut Microbiota Composition and Disrupt Host Body-iron Status
A study testing Black tea in people with Focus of Study: 1- Effect of Tea Consumption on Gut Microbiota and Focus of Study: 2- Effect of Tea Consumption on Body-iron Status, run by University of Reading at 1 site in United Kingdom.
Trial summary
Iron is an essential micronutrient for nearly all living organisms, including microbes. The adult human body contains approximately 3-5 g of iron (45-55 mg/kg of body weight in adult women and men, respectively). Read more about this study
- Who is it for?
- Ages 18 to 60 yearsHealthy volunteers can take part
- Conditions the study is for
- Focus of Study: 1- Effect of Tea Consumption on Gut Microbiota, Focus of Study: 2- Effect of Tea Consumption on Body-iron Status
- What is being tested?
- Black tea
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 40 participants
- Where
- 1 siteUnited Kingdom
- Study dates
- 20 Sep 2021to 10 Jan 2022
- 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 60 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Age: 18-60 years
- Gender: Male or Female
- Volunteers agree to sign an informal written consent form
- General good health
- Normal haemoglobin and serum ferritin levels
Who cannot join
- Regular tea drinkers
- Use of antibiotics, prebiotics or probiotics (in food products or as supplements), laxatives, anti-spasmodic, anti-diarrhoea drugs, (e.g. Orlistat, Lactulose) in the last 4 weeks prior to, or during the study period.
- Use of any iron supplement in the last 6 months prior to the study period.
- If participants have received bowel preparation for investigative procedures in the 4 weeks prior to the study.
- Surgical resection of any part of the bowel.
- If you have any chronic gut disorder/disease, such as IBS, IBD, etc. or other conditions that might affect the gut environment, e.g. coeliac disease. If participants are taking any medication that could affect the iron absorption (e.g. lansoprazole, omeprazole). Those with gluten allergies (e.g. Celiac disease) must be excluded as the placebo may contain gluten
Show all 9Show fewer
- If participants are pregnant or are lactating.
- If participants have a BMI > 30 kg/m2.
- Severe allergy or any history of severe abnormal drug reaction, drug or alcohol abuse
Trial locations and contacts
1 site in 1 country.
United Kingdom1 site
University of Reading
Reading
Amro Duhduh, 07950285776, a.duhduh@pgr.reading.ac.uk
Andrea Monteagudo, a.monteagudo@reading.ac.uk
About this study
Official title: A Double-blind Placebo Controlled Study to Determine the Effect of Tea Consumption on Gut Microbiota Composition and Body-Iron Status
Iron is an essential micronutrient for nearly all living organisms, including microbes. The adult human body contains approximately 3-5 g of iron (45-55 mg/kg of body weight in adult women and men, respectively). Iron-deficiency related anaemia (IDA) is a major public health problem that affects more than 2 billion people globally and this represents 24.8% of the world's population. According to World Health Organisation (WHO), iron deficiency is the most common cause of anaemia worldwide, with infants, children and women at higher risk, making it a global public health problem. Much iron deficiency is a result of poor iron dietary absorption since iron is poorly absorbed (~15%). Absorption inhibition factors (iron chelators) like phytate and tannins, found in tea and vegetables have been reported to act as potent iron uptake inhibitors. Despite its health benefits, tea-containing polyphenols (tannins) have been associated with reduction and disruption of iron absorption, acting as inhibitors of non-haem iron uptake, potentially resulting in poor iron status. However, most studies on the effect of tea on iron absorption are largely based on isotope-labelled single meal studies and animal studies. Iron is a requirement of many microorganisms, as such changes in iron availability can also have an impact on the gut microbiota. Long-term controlled human intervention studies to investigate the effect of tea on iron absorption and the effect on gut microbiota composition are scarce. In addition, the impact of dietary tannins on the gut microbiota is not understood. Thus, this proposed human intervention trial will investigate the combined effect of tea-tannins on iron status, inflammation and gut microbiota composition. This will be the first study to consider this combination of factors.
- Conditions
- Focus of Study: 1- Effect of Tea Consumption on Gut Microbiota, Focus of Study: 2- Effect of Tea Consumption on Body-iron Status
- Being tested
- Black tea, Placebo
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Black teaDietary supplement
Black tea twice a day for 4 weeks
PlaceboDietary supplement
Placebo tea twice a day for 4 weeks
| Study group | Role | What they receive |
|---|---|---|
| Black tea group | Experimental | Volunteers meeting inclusion/exclusion criteria will be given an appropriate number of black tea samples twice a day with main meals for the 4 weeks of the treatment. Receives: Dietary Supplement: Black tea |
| Placebo group | Placebo comparator | Volunteers meeting inclusion/exclusion criteria will be given an appropriate number of placebo tea samples twice a day with main meals for the 4 weeks of the treatment. Receives: Dietary Supplement: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Composition and diversity of the faecal microbiota of the individuals consuming tea/placebo during the 4 weeks intervention
Changes in composition and diversity of faecal microbiota in response to black tea intervention assessed by next generation sequences NGS
Measured: 4 weeks intervention
Levels of faecal and urine metabolites of the individuals consuming tea/placebo during the 4 weeks intervention
Changes of metabolic profile during the intervention will be estimated in faecal and urine samples using Nuclear Magnetic Resonance (NMR)
Measured: 4 weeks intervention
Levels of ferritin (ng/mL) as body-iron status indicators of the individuals consuming tea/placebo during the 4 weeks intervention
Ferritin will be monitored through blood samples collected during study visits.
Measured: 4 weeks intervention
Changes in the concentration (pg/mL) of inflammation markers in plasma of the individuals consuming tea/placebo using enzyme-linked immunosorbent assays (ELISAs)
gut inflammation will be assessed by measuring concentration (pg/mL) of gut inflammatory markers as plasma intestinal fatty acid-binding protein and cytokines from plasma (e.g. IL-10, IL-6, TNFα). Samples will be analysed using enzyme-linked immunosorbent assays (ELISAs)
Measured: 4 weeks intervention
Changes in the concentration (mcg/g) of faecal calprotectin (gut inflammatory marker) during tea intervention using enzyme-linked immunosorbent assays (ELISAs)
Gut inflammation will be assessed measuring concentration (mcg/g) of calprotectin. Increase in the levels of Calprotectin indicates the migration of neutrophils to the intestinal mucosa, which occurs during intestinal inflammation.
Measured: 4 weeks intervention
Secondary outcomes (2)
Assessment of stool consistency
The Bristol stool chart will be provided to volunteer to measure stool consistency, the chart rate the stool consistency from 1-7 (solid - liquid) based on the shape of stool.
Measured: 4 weeks intervention
Assessment of gastrointestinal symptoms
Daily assessment of gastrointestinal symptoms (abdominal pain, bloating or flatulence) will be recorded daily using daily diary.
Measured: 4 weeks intervention
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted25 Aug 2021
- Study start20 Sep 2021 (estimated)
- Primary completion10 Dec 2021 (estimated)
- Study completion10 Jan 2022 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Focus of Study: 1- Effect of Tea Consumption on Gut MicrobiotaStudies 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
- Screening
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- A randomised, double-blind (subject/investigator), placebo controlled, parallel study.
- Masking
- Triple blind
- Who is masked
- Participant, Investigator, Outcomes assessor
- Enrolment
- 40 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of Reading
- Sponsor type
- University, hospital or other
- Collaborators
- Unilever R&D
- Responsible party
- Principal investigator, Gemma Walton, University of Reading
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05019573
- Sponsor's protocol ID
- UREC 20/04
- Status last verified
- Aug 2021
- First submitted
- 15 Jun 2021
- Last updated
- 25 Aug 2021
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes
Study at a glance
From the registry record, last updated by the sponsor on 25 Aug 2021. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Double-blind Placebo Controlled Study to Determine the Effect of Tea Consumption on Gut Microbiota Composition and Body-Iron Status
- ClinicalTrials.gov ID
- NCT05019573
- Acronym / sponsor ID
- UREC 20/04
- Conditions
- Focus of Study: 1- Effect of Tea Consumption on Gut Microbiota, Focus of Study: 2- Effect of Tea Consumption on Body-iron Status
- Study type
- Interventional
- Recruitment status
- Unknown status
- Enrolment
- 40 participants (estimated)
- Lead sponsor
- University of ReadingUniversity, hospital or other
- Collaborators
- Unilever R&D
- Study start
- 20 Sep 2021 (estimated)
- Primary completion
- 10 Dec 2021 (estimated)
- Study completion
- 10 Jan 2022 (estimated)
- First posted
- 25 Aug 2021 (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.
Iron is an essential micronutrient for nearly all living organisms, including microbes. The adult human body contains approximately 3-5 g of iron (45-55 mg/kg of body weight in adult women and men, respectively). Iron-deficiency related anaemia (IDA) is a major public health problem that affects more than 2 billion people globally and this represents 24.8% of the world's population. According to World Health Organisation (WHO), iron deficiency is the most common cause of anaemia worldwide, with infants, children and women at higher risk, making it a global public health problem. Much iron deficiency is a result of poor iron dietary absorption since iron is poorly absorbed (~15%). Absorption inhibition factors (iron chelators) like phytate and tannins, found in tea and vegetables have been reported to act as potent iron uptake inhibitors. Despite its health benefits, tea-containing polyphenols (tannins) have been associated with reduction and disruption of iron absorption, acting as inhibitors of non-haem iron uptake, potentially resulting in poor iron status. However, most studies on the effect of tea on iron absorption are largely based on isotope-labelled single meal studies and animal studies. Iron is a requirement of many microorganisms, as such changes in iron availability can also have an impact on the gut microbiota. Long-term controlled human intervention studies to investigate the effect of tea on iron absorption and the effect on gut microbiota composition are scarce. In addition, the impact of dietary tannins on the gut microbiota is not understood. Thus, this proposed human intervention trial will investigate the combined effect of tea-tannins on iron status, inflammation and gut microbiota composition. This will be the first study to consider this combination of factors.
Study design
- Primary purpose
- Screening
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind (participant, investigator, outcomes assessor)
- Number of arms
- 2
- Model description
- A randomised, double-blind (subject/investigator), placebo controlled, parallel study.
| Arm | Type | Receives |
|---|---|---|
| Black tea group | Experimental | Dietary Supplement: Black teaVolunteers meeting inclusion/exclusion criteria will be given an appropriate number of black tea samples twice a day with main meals for the 4 weeks of the treatment. |
| Placebo group | Placebo comparator | Dietary Supplement: PlaceboVolunteers meeting inclusion/exclusion criteria will be given an appropriate number of placebo tea samples twice a day with main meals for the 4 weeks of the treatment. |
Who may qualify
- Ages
- 18 to 60 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Age: 18-60 years
- Gender: Male or Female
- Volunteers agree to sign an informal written consent form
- General good health
- Normal haemoglobin and serum ferritin levels
Key exclusion criteria (9 listed)
- Regular tea drinkers
- Use of antibiotics, prebiotics or probiotics (in food products or as supplements), laxatives, anti-spasmodic, anti-diarrhoea drugs, (e.g. Orlistat, Lactulose) in the last 4 weeks prior to, or during the study period.
- Use of any iron supplement in the last 6 months prior to the study period.
- If participants have received bowel preparation for investigative procedures in the 4 weeks prior to the study.
- Surgical resection of any part of the bowel.
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 |
|---|---|---|
| Black teaBlack tea twice a day for 4 weeks | Dietary supplement | Black tea group |
| PlaceboPlacebo tea twice a day for 4 weeks | Dietary supplement | Placebo group |
Primary outcome
Composition and diversity of the faecal microbiota of the individuals consuming tea/placebo during the 4 weeks intervention
Time frame: 4 weeks intervention
Changes in composition and diversity of faecal microbiota in response to black tea intervention assessed by next generation sequences NGS
Levels of faecal and urine metabolites of the individuals consuming tea/placebo during the 4 weeks intervention
Time frame: 4 weeks intervention
Changes of metabolic profile during the intervention will be estimated in faecal and urine samples using Nuclear Magnetic Resonance (NMR)
Levels of ferritin (ng/mL) as body-iron status indicators of the individuals consuming tea/placebo during the 4 weeks intervention
Time frame: 4 weeks intervention
Ferritin will be monitored through blood samples collected during study visits.
Changes in the concentration (pg/mL) of inflammation markers in plasma of the individuals consuming tea/placebo using enzyme-linked immunosorbent assays (ELISAs)
Time frame: 4 weeks intervention
gut inflammation will be assessed by measuring concentration (pg/mL) of gut inflammatory markers as plasma intestinal fatty acid-binding protein and cytokines from plasma (e.g. IL-10, IL-6, TNFα). Samples will be analysed using enzyme-linked immunosorbent assays (ELISAs)
Changes in the concentration (mcg/g) of faecal calprotectin (gut inflammatory marker) during tea intervention using enzyme-linked immunosorbent assays (ELISAs)
Time frame: 4 weeks intervention
Gut inflammation will be assessed measuring concentration (mcg/g) of calprotectin. Increase in the levels of Calprotectin indicates the migration of neutrophils to the intestinal mucosa, which occurs during intestinal inflammation.
2 secondary outcomes
Assessment of stool consistency
Time frame: 4 weeks intervention
Assessment of gastrointestinal symptoms
Time frame: 4 weeks intervention
Results and safety
Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 25 Aug 2021.
- Individual participant dataSharing planned: Yes
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.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Black tea in people with Focus of Study: 1- Effect of Tea Consumption on Gut Microbiota and Focus of Study: 2- Effect of Tea Consumption on Body-iron Status, run by University of Reading 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 5 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 25 Aug 2021. 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. Some participants in this study may receive a placebo. 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?
Each site lists its own contact: choose the nearest one under Trial locations. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Composition and diversity of the faecal microbiota of the individuals consuming tea/placebo during the 4 weeks intervention (time frame: 4 weeks intervention). The study lists 5 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 25 Aug 2021.