Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12618001054202
Ethics application status
Approved
Date submitted
15/06/2018
Date registered
25/06/2018
Date last updated
15/11/2019
Date data sharing statement initially provided
5/06/2019
Date results information initially provided
15/11/2019
Type of registration
Prospectively registered

Titles & IDs
Public title
Studying health effects of consumption of a high fibre diet in healthy humans
Scientific title
Study of immune and therapeutic effects of short-chain fatty acids in humans given a high fibre diet.
Secondary ID [1] 295202 0
NONE
Universal Trial Number (UTN)
Trial acronym
SITES
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Hypertension 308337 0
Gut disease 308338 0
Condition category
Condition code
Diet and Nutrition 307339 307339 0 0
Other diet and nutrition disorders
Inflammatory and Immune System 307340 307340 0 0
Normal development and function of the immune system
Cardiovascular 307391 307391 0 0
Hypertension

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
3 week dietary intervention provided in the form of meals and supplements to study participants. Participants are provided with 3 main meals day (breakfast, lunch, dinner) and 2 snack items a day (morning tea, afternoon tea). Participants may also eat other foods outside of the provided diet but are given a list of recommended snack foods to help them follow the intervention diet as best as possible. Meals have been developed with a dietitian to ensure they are nutritionally balanced and are cooked by a research chef in a commercial grade kitchen. Meals are portioned, vacuum-sealed and then provided to participants frozen. Participants are given study food diaries to follow and to help assess compliance. The average amount of energy provided by the study meals/snacks is 8400 kj/day as to ensure all intervention meals are consumed. The average amount of fibre is 40 g/day. 20 g of which is from the foods provided, 10 g from Resistant starch added to certain meals and 10 g from Inulin also added to certain meals. These fibres are mixed into meals during the cooking process. These figures have been calculated through the use of food composition software (Foodworks).
Examples of meals that have resistant starch fibre added to them include breakfast pancakes, muffins and Tuna and vegetable patties. Some meals will also have a fermentable fibre (inulin) added to them such as risotto, pasta sauce and curry.
Intervention code [1] 301536 0
Lifestyle
Comparator / control treatment
A 3-week low fibre diet. This will deliver 20 g/day of dietary fibre on on the low fibre diet.
3 week dietary intervention provided in the form of meals to study participants. No additional supplements are provided. Participants are provided with 3 main meals day (breakfast, lunch, dinner) and 2 snack items a day (morning tea, afternoon tea). Participants may also eat other foods outside of the provided diet but are given a list of recommended snack foods to help them follow the intervention diet as best as possible. Meals have been developed with a dietitian to ensure they are nutritionally balanced and are cooked by a research chef in a commercial grade kitchen. Meals are portioned, vacuum-sealed and then provided to participants frozen. Participants are given study food diaries to follow and to help assess compliance. The average amount of energy provided by the study meals/snacks is 8400 kj/day as to ensure all intervention meals are consumed. This figure has been calculated through the use of food composition software (Foodworks).
Examples of meals (all made with gluten-free/low flour) include breakfast pancakes, muffins and Tuna and vegetable patties
Control group
Dose comparison

Outcomes
Primary outcome [1] 306328 0
Blood short-chain fatty acid level
Timepoint [1] 306328 0
Day 21 of dietary intervention period
Primary outcome [2] 306329 0
Peripheral blood immune cells assessed by flow cyotmetry. Absolute numbers of the following cells will be assessed:
T cells: Th2, Th1, Th17, Treg subsets
B cells: IgA+, IgG+, IgE+
Innate immune cells: Dendritic cells, neutrophils, macrophages

This is a composite primary outcome.
Timepoint [2] 306329 0
Day 21 of dietary intervention period
Primary outcome [3] 306330 0
Faecal microbiota composition as assessed by 16S rRNA sequencing. This is an exploratory outcome
Timepoint [3] 306330 0
Day 20 of dietary intervention period
Secondary outcome [1] 348210 0
Blood pressure, measured by a digital blood pressure monitor.
Timepoint [1] 348210 0
24 hours during day 20 of dietary intervention period
Secondary outcome [2] 348211 0
Gastrointestinal symptoms. Participants will complete bowel symptom diaries to assess abdominal bloating, bowel movements, urgency of bowel movements, wind and nausea. These are measured using VAS scales. Stool form will also be assessed using the bristol stool scale.
Together, this is a composite primary outcome.
Timepoint [2] 348211 0
Everyday throughout dietary intervention period

Eligibility
Key inclusion criteria
Healthy adults
Minimum age
18 Years
Maximum age
45 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Existing or history of gastrointestinal or chronic inflammatory disease; recent acute illness or infection; antibiotic use within one month of study; consumption of probiotics or prebiotics within one month of study; use of medication gastrointestinal transit (e.g. laxatives or hypomotility agents); pregnant or planning pregnancy; suffering from an eating disorder; have special dietary requirements (vegetarian/vegan) or currently taking medication for hypertension.

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)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Who is / are masked / blinded?



Intervention assignment
Other design features
Phase
Not Applicable
Type of endpoint/s
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
28/06/2018
Actual
23/08/2018
Date of last participant enrolment
Anticipated
29/06/2019
Actual
25/06/2019
Date of last data collection
Anticipated
14/09/2019
Actual
9/09/2019
Sample size
Target
30
Accrual to date
Final
22
Recruitment in Australia
Recruitment state(s)
VIC
Recruitment hospital [1] 11152 0
The Alfred - Prahran
Recruitment postcode(s) [1] 22977 0
3004 - Prahran

Funding & Sponsors
Funding source category [1] 299786 0
University
Name [1] 299786 0
Monash University
Country [1] 299786 0
Australia
Primary sponsor type
University
Name
Monash University
Address
Department of Gastroenterology, Central clinical school, Level 6, The Alfred centre, 99 Commercial road, Melbourne, Victoria 3004
Country
Australia
Secondary sponsor category [1] 299133 0
None
Name [1] 299133 0
Address [1] 299133 0
Country [1] 299133 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 300674 0
Monash University Human Research Ethics Commitee
Ethics committee address [1] 300674 0
Monash Research Office, 26 Sports Walk, Monash University, Wellington Road, Clayton VIC 3800
Ethics committee country [1] 300674 0
Australia
Date submitted for ethics approval [1] 300674 0
31/01/2018
Approval date [1] 300674 0
01/03/2018
Ethics approval number [1] 300674 0
11190

Summary
Brief summary
Dietary fibre is important for gut health. Within the large intestine, some dietary fibres are broken down by the gut bacteria (microbiota) in a process called fermentation. A product of fermentation are metabolites called short-chain fatty acids. These can also be found in fermented foods and drinks, such as vinegar. In animal studies, short-chain fatty acids have been associated with reduced inflammation and lower blood pressure.
The aims of this research project is to investigate if increasing short-chain fatty acids through increasing fibre and fermentable foods in the diet have effects on:
1. Immune cells and inflammation
2. Blood pressure
3. Gut function
To answer these questions, we are asking for healthy volunteers to participate in a dietary intervention study. This will involve consuming a diet with varying levels of fibre and fermented foods. At certain points in the study, Blood and faecal samples will be taken and we will also measure your blood pressure. We aim to recruit 30 healthy participants.
This study will help us to understand if dietary fibre and fermentable foods could be used to reduce inflammation and blood pressure in conditions such as asthma, allergy and hypertension in the future. This study has been initiated by A/Prof. Jane Muir, head of Translational research at the Department of Gastroenterology and is being conducted by Mr. Paul Gill as part of his PhD studies
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 84426 0
A/Prof Jane Muir
Address 84426 0
Department of Gastroenterology, Monash University, Level 6, The Alfred centre, 99 Commercial Road, Melbourne, Victoria 3004
Country 84426 0
Australia
Phone 84426 0
+61 3 99030274
Fax 84426 0
Email 84426 0
[email protected]
Contact person for public queries
Name 84427 0
Mr Paul Gill
Address 84427 0
Department of Gastroenterology, Monash University, Level 6, The Alfred centre, 99 Commercial Road, Melbourne, Victoria 3004
Country 84427 0
Australia
Phone 84427 0
+61 3 99030396
Fax 84427 0
Email 84427 0
[email protected]
Contact person for scientific queries
Name 84428 0
Mr Paul Gill
Address 84428 0
Department of Gastroenterology, Monash University, Level 6, The Alfred centre, 99 Commercial Road, Melbourne, Victoria 3004
Country 84428 0
Australia
Phone 84428 0
+61 3 99030396
Fax 84428 0
Email 84428 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
We have not obtained ethics approval for individual participant data to be made public. At this stage we do not intend on making this data public.


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
SourceTitleYear of PublicationDOI
EmbaseA randomized dietary intervention to increase colonic and peripheral blood SCFAs modulates the blood B- and T-cell compartments in healthy humans.2022https://dx.doi.org/10.1093/ajcn/nqac246
N.B. These documents automatically identified may not have been verified by the study sponsor.