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Trial registered on ANZCTR


Registration number
ACTRN12624000373572
Ethics application status
Approved
Date submitted
29/01/2024
Date registered
2/04/2024
Date last updated
15/05/2024
Date data sharing statement initially provided
2/04/2024
Type of registration
Prospectively registered

Titles & IDs
Public title
Effects of Rooibos Extract on Anxiety Levels
Scientific title
The Effects of Green Rooibos Tea Extract on Anxiety Levels (REAL) Study in adults with mild to moderate anxiety
Secondary ID [1] 311159 0
Nil known
Universal Trial Number (UTN)
U1111-1301-6151
Trial acronym
REAL
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Anxiety 332355 0
Condition category
Condition code
Mental Health 329075 329075 0 0
Anxiety
Alternative and Complementary Medicine 329598 329598 0 0
Other alternative and complementary medicine

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Designed as a pilot double blind, randomised, placebo controlled, parallel trial, enrolled participants will be randomised into either the active or control group. The study incorporates a one week baseline period, 8-week intervention period and 2-week follow up. After baseline measurements, participants in the active group will receive "active" capsules containing 250mg of green rooibos extract (19.25mg of Aspalathin). Participants will consume one capsule/day for the first week of the intervention period and increase this to two capsules per day for the remaining 7 weeks of the intervention period (trial intervention period = 8 weeks).

Participants will be asked to return any unused capsules at each clinic visit. Unused capsules will be counted to determine compliance.
Intervention code [1] 327636 0
Treatment: Other
Comparator / control treatment
The control group will be receive placebo capsules which will contain a standardised inert compound commonly used in these types of studies (such as maltodextrin, capsule filler, or similar). Placebo capsules will be colour- and size-matched to the active capsules. Participants will be instructed to consume the placebo capsule in the same manner as in the active group.
Control group
Placebo

Outcomes
Primary outcome [1] 337140 0
Self-reported anxiety levels
Timepoint [1] 337140 0
Administered for completion on the day before Clinic 2 (Day 7 pre-treatment commencement), Clinic 3 (Day 27 post-treatment commencement) and Clinic 4 (Day 55 post-treatment commencement)
Secondary outcome [1] 430037 0
Dietary intake
Timepoint [1] 430037 0
Administered for completion on the day before Clinic 2 (Day 2, Day 4 and Day 6 pre-treatment commencement), Clinic 3 (Day 22, Day 24, and Day 26 post-treatment commencement) and Clinic 4 (Day 50, Day 52 and Day 54 post-treatment commencement)
Secondary outcome [2] 430038 0
Alcohol consumption
Timepoint [2] 430038 0
Administered for completion on the day before Clinic 2 (Day 7 pre-treatment commencement), Clinic 3 (Day 27 post-treatment commencement) and Clinic 4 (Day 55 post-treatment commencement)
Secondary outcome [3] 430039 0
Chronotype
Timepoint [3] 430039 0
Administered for completion on the day before Clinic 2 (Day 7 pre-treatment commencement), Clinic 3 (Day 27 post-treatment commencement) and Clinic 4 (Day 55 post-treatment commencement)
Secondary outcome [4] 430040 0
Immunological status
Timepoint [4] 430040 0
Administered for completion on the day before Clinic 2 (Day 7 pre-treatment commencement) and Clinic 4 (Day 55 post-treatment commencement)
Secondary outcome [5] 430089 0
Sleep onset latency
Timepoint [5] 430089 0
Data collection for one week prior to Clinics 2 (Days 1 - 7 pre-treatment commencement) and 4 (Days 49 - 55 post-treatment commencement)
Secondary outcome [6] 430090 0
Sleep Quality (Qualitative)
Timepoint [6] 430090 0
Administered for completion on the day before Clinic 2 (Day 7 pre-treatment commencement), Clinic 3 (Day 27 post-treatment commencement) and Clinic 4 (Day 55 post-treatment commencement)
Secondary outcome [7] 430092 0
Physical Activity Levels
Timepoint [7] 430092 0
Data collection for one week prior to Clinics 2 (Days 1 - 7 pre-treatment commencement) and 4 (Days 49 - 55 post-treatment commencement)
Secondary outcome [8] 430095 0
Body weight
Timepoint [8] 430095 0
During Clinic 1 - Screening (Day 1 pre-treatment commencement) and Clinic 4 (Day 56 post-treatment commencement)
Secondary outcome [9] 430096 0
Heart Rate Variability (HRV)
Timepoint [9] 430096 0
Measured during Clinics 2 (Day 1 of treatment commencement), 3 (Day 28 post-treatment commencement) and 4 (Day 56 post-treatment commencement)
Secondary outcome [10] 430097 0
Resting blood pressure
Timepoint [10] 430097 0
Measured during Clinics 1 - Screening [Day 1 (of 7) pre-treatment commencement], 2 (Day 1 of treatment commencement), 3 (Day 28 post-treatment commencement) and 4 (Day 56 post-treatment commencement).
Secondary outcome [11] 430099 0
Grip Strength
Timepoint [11] 430099 0
Measured during Clinics 2 (Day 1 of treatment commencement) and 4 (Day 56 post-treatment commencement)
Secondary outcome [12] 430101 0
Stool Metagenomics
Timepoint [12] 430101 0
Collected a day prior to Clinic 2 (Day 7 pre-treatment commencement) and Clinic 4 (Day 55 post-treatment commencement)
Secondary outcome [13] 431641 0
Percent sleep efficiency
Timepoint [13] 431641 0
Data collection for one week prior to Clinics 2 (Days 1 - 7 pre-treatment commencement) and 4 (Days 49 - 55 post-treatment commencement)
Secondary outcome [14] 431642 0
Sleep Duration
Timepoint [14] 431642 0
Data collection for one week prior to Clinics 2 (Days 1 - 7 pre-treatment commencement) and 4 (Days 49 - 55 post-treatment commencement)
Secondary outcome [15] 431643 0
Total Sleep Time
Timepoint [15] 431643 0
Data collection for one week prior to Clinics 2 (Days 1 - 7 pre-treatment commencement) and 4 (Days 49 - 55 post-treatment commencement)
Secondary outcome [16] 431644 0
Wake after sleep onset
Timepoint [16] 431644 0
Data collection for one week prior to Clinics 2 (Days 1 - 7 pre-treatment commencement) and 4 (Days 49 - 55 post-treatment commencement)
Secondary outcome [17] 433164 0
Body fat %
Timepoint [17] 433164 0
During Clinic 1 - Screening (Day 1 pre-treatment commencement) and Clinic 4 (Day 56 post-treatment commencement)
Secondary outcome [18] 433165 0
Body fat mass
Timepoint [18] 433165 0
During Clinic 1 - Screening (Day 1 pre-treatment commencement) and Clinic 4 (Day 56 post-treatment commencement)
Secondary outcome [19] 433166 0
Fat free mass
Timepoint [19] 433166 0
During Clinic 1 - Screening (Day 1 pre-treatment commencement) and Clinic 4 (Day 56 post-treatment commencement)
Secondary outcome [20] 433167 0
Muscle mass
Timepoint [20] 433167 0
During Clinic 1 - Screening (Day 1 pre-treatment commencement) and Clinic 4 (Day 56 post-treatment commencement)
Secondary outcome [21] 433168 0
Total body weight
Timepoint [21] 433168 0
During Clinic 1 - Screening (Day 1 pre-treatment commencement) and Clinic 4 (Day 56 post-treatment commencement)
Secondary outcome [22] 433169 0
Total body water
Timepoint [22] 433169 0
During Clinic 1 - Screening (Day 1 pre-treatment commencement) and Clinic 4 (Day 56 post-treatment commencement)
Secondary outcome [23] 433170 0
Total body water %
Timepoint [23] 433170 0
During Clinic 1 - Screening (Day 1 pre-treatment commencement) and Clinic 4 (Day 56 post-treatment commencement)
Secondary outcome [24] 433171 0
Bone mass
Timepoint [24] 433171 0
During Clinic 1 - Screening (Day 1 pre-treatment commencement) and Clinic 4 (Day 56 post-treatment commencement)
Secondary outcome [25] 433172 0
Basal metabolic rate
Timepoint [25] 433172 0
During Clinic 1 - Screening (Day 1 pre-treatment commencement) and Clinic 4 (Day 56 post-treatment commencement)
Secondary outcome [26] 433173 0
Visceral fat rating
Timepoint [26] 433173 0
During Clinic 1 - Screening (Day 1 pre-treatment commencement) and Clinic 4 (Day 56 post-treatment commencement)
Secondary outcome [27] 433174 0
Body mass index
Timepoint [27] 433174 0
During Clinic 1 - Screening (Day 1 pre-treatment commencement) and Clinic 4 (Day 56 post-treatment commencement)
Secondary outcome [28] 435114 0
Biomarkers of anxiety
Timepoint [28] 435114 0
Secondary outcome [29] 435115 0
Biomarkers of anxiety
Timepoint [29] 435115 0
Collected for Clinic 2 [once the night before (Day 7 pre-treatment commencement) and twice on the morning (upon waking and 45 minutes following the initial morning collection)} of treatment commencement (Day 1 of treatment commencement), Clinic 3, [once the night before (Day 27 post-treatment commencement) and twice on the morning of Clinic 3 (upon waking and 45 minutes following the initial morning collection -- Day 28 post-treatment commencement)] and Clinic 4 [once the night before (Day 55 post-treatment commencement) and twice on the morning of Clinic 4 (upon waking and 45 minutes following the initial morning collection -- Day 56 post-treatment commencement)}.

Eligibility
Key inclusion criteria
Healthy participants with mild to moderate anxiety levels that score between 11 and 25 (inclusive) on the Beck Anxiety Inventory (screening measure). Participants will be in general good health, willing to comply with all study procedures, and avoid consumption of rooibos tea/extract in any other form throughout the trial (other than through the intervention).
Minimum age
18 Years
Maximum age
65 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Participants will be excluded from the study if they:
• have a BMI >= 35kg/m2,
• have blood pressure >= 160/95 mmHg,
• take or have taken within 8 weeks prior to enrollment any anti-anxiety or antidepressant medication or supplement (e.g. St. John's wort, valerian, ashwagandha, CBD oil, etc.),
• take sleep, gastrointestinal, cardiovascular or other medication or supplement deemed to interfere with measured parameters,
• have taken antibiotics within 8 weeks prior to enrollment,
• have taken probiotics/prebiotics/postbiotics within 2 weeks prior to enrollment,
• are receiving or have received any kind of formal psychological treatment for anxiety within 8 weeks prior to enrollment,
• have a known allergy or hypersensitivity to any of the components of the study product,
• are pregnant or lactating,
• are currently participating in other intervention studies,
• have any chronic diseases, including but not limited to CVD, diabetes (Type I and Type II), cancer, kidney disease, gastrointestinal disease, clinically diagnosed mental illness or are severely immunocompromised,
• have planned surgical procedures during the course of the study;
• have any physical injuries preventing the participation in exercise testing.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Participants will be assigned a pre-determined and unique seven digit participant code during enrollment
which will be non-identifiable. All participants will be randomly allocated either the active or control groups. Method of allocation will be located within a sealed envelope and broken when they study is completed (all participants data) is final. The person randomising the participants will not know the allocation.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Sequence generation will be block randomised 1:1 using an online randomizer tool (https://www.randomizer.org/).
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
ACT,NSW

Funding & Sponsors
Funding source category [1] 315415 0
Commercial sector/Industry
Name [1] 315415 0
ADM WILD Valencia
Country [1] 315415 0
Spain
Primary sponsor type
University
Name
University of Canberra
Address
11 Kirinari Street, Bruce ACT 2617
Country
Australia
Secondary sponsor category [1] 317478 0
None
Name [1] 317478 0
Address [1] 317478 0
Country [1] 317478 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 314330 0
University of Canberra Human Research Ethics Committee
Ethics committee address [1] 314330 0
11 Kirinari Street, Bruce ACT 2617
Ethics committee country [1] 314330 0
Australia
Date submitted for ethics approval [1] 314330 0
08/11/2023
Approval date [1] 314330 0
20/12/2023
Ethics approval number [1] 314330 0

Summary
Brief summary
The REAL study is a pilot randomised, placebo-controlled clinical trial investigating the effects of green rooibos tea extract supplementation (dose = 500mg of rooibos extract) on anxiety levels in mildly to moderately anxious adults. The study incorporates a one week baseline period, 8-week intervention period and 2-week follow up.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 131206 0
Prof Nenad Naumovski
Address 131206 0
University of Canberra, PO Box 5018, Bruce ACT, 2617
Country 131206 0
Australia
Phone 131206 0
+61 2 62068719
Fax 131206 0
Email 131206 0
nenad.naumovski@canberra.edu.au
Contact person for public queries
Name 131207 0
Dr Dr Katie Speer
Address 131207 0
University of Canberra, PO Box 5018, Bruce ACT, 2617
Country 131207 0
Australia
Phone 131207 0
+61 4 03844963
Fax 131207 0
Email 131207 0
katie.speer@canberra.edu.au
Contact person for scientific queries
Name 131208 0
Prof Prof Nenad Naumovski
Address 131208 0
University of Canberra, PO Box 5018, Bruce ACT, 2617
Country 131208 0
Australia
Phone 131208 0
+61 2 62068719
Fax 131208 0
Email 131208 0
nenad.naumovski@canberra.edu.au

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
Participants have not consented to provide IPD


What supporting documents are/will be available?

Doc. No.TypeCitationLinkEmailOther DetailsAttachment
21218Clinical study report    A clinical study report will be provided when the ... [More Details]


Results publications and other study-related documents

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No documents have been uploaded by study researchers.

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