Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12620000301965
Ethics application status
Approved
Date submitted
29/01/2020
Date registered
5/03/2020
Date last updated
19/05/2023
Date data sharing statement initially provided
5/03/2020
Date results information initially provided
13/04/2023
Type of registration
Prospectively registered

Titles & IDs
Public title
Dietary interventions for weight loss in women with obesity
Scientific title
The effect of very-low energy diets for weight loss on gut microbiota composition and associated health in women with obesity: a randomised controlled trial
Secondary ID [1] 300388 0
Nil known
Universal Trial Number (UTN)
U1111-1247-4089
Trial acronym
The MicroFit Study
Linked study record
n/a

Health condition
Health condition(s) or problem(s) studied:
Gut microbiota 316009 0
Obesity 316010 0
Condition category
Condition code
Diet and Nutrition 314284 314284 0 0
Obesity
Oral and Gastrointestinal 314440 314440 0 0
Normal oral and gastrointestinal development and function
Metabolic and Endocrine 314441 314441 0 0
Normal metabolism and endocrine development and function

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The proposed study is a 3-week; 1:1 parallel-group, randomised, controlled trial of a food-based compared to a supplement based very-low energy diet (VLED) for weight loss in women with obesity. Participants will be randomly assigned to receive either a food-based VLED (diet A) or supplement-based VLED (diet B) using block randomisation.

Food-based VLED consumables:
All breakfast, lunch, dinner and a protein snack (1 per day) will be provided as part of the Rapid Weight Loss Program outlined by Be Fit Food (vegetarian, gluten free and meat-based programs provided). As part of the Rapid Weight Loss Program, participants’ food plan will contain 820-920kcal per day (3347-3766kJ) with meal replacements containing no added sugar, low sodium and carbohydrate, high protein, and various vegetables per serve. In addition to meals, participants will be recommended to consume food from a ‘Recommended Extras’ list (Appendix 1, food-based condition). Food on this list includes low carbohydrate side vegetables and salads that participants can prepare themselves to have alongside the Be Fit Food meal replacements. The meals replacements are calorie controlled and consist of levels of protein, fatty acids, carbohydrates, vitamins and minerals suggested for effective weight loss.

The food-based VLED consumables are designed by Accredited Practicing Dietitians. These ready-made home delivered meals are created and prepared by qualified chefs. In addition, at study Visit 1, participants will receive dietary recommendations designed by an Accredited Practicing Dietitian to aid with adherence to the intervention.

Although it is recognised that the provision of food, particularly ready-made meals, help to ensure dietary adherence due to their convenience as well as promoting a more tightly controlled dietary intervention than if participants were preparing meals themselves, the MicroFit Study aims to assess adherence to the dietary prescription through the utilisation of the Easy Diet Diary app. The Easy Diet Diary is a free app available on smart phones and contains a database of commonly eaten foods for users to add to a diary at each eating occasion, without providing feedback about nutrition content. Dietary intake data from the app will be available to the researchers online and will be analysed for the energy and nutrient composition using FoodWorks (Xyris Software Pty Ltd, Australia).
Intervention code [1] 316669 0
Lifestyle
Intervention code [2] 316777 0
Treatment: Other
Comparator / control treatment
Supplement-based VLED consumables:
All breakfast, lunch and dinner will be provided in the form of Optifast ® VLCD™ total meal replacement sachets, bars, soups and/or desserts. As well as the meal replacements, participants will be recommended to consume two cups of low starch vegetables plus one tablespoon of vegetable oil from a ‘Recommended Extras’ list (Appendix 1, supplement-based condition), as part of the OPTIFAST VLCD Program Intensive Level. The total energy content of the OPTIFAST VLCD Program Intensive Level is also approximately 820 – 920kcal per day (3347-3766kJ). The meals replacements are calorie controlled and consist of levels of protein, fatty acids, carbohydrates, vitamins and minerals suggested for effective weight loss.

The investigational and comparison dietary programs are energetically equivalent and the meal replacements are closely matched for their macronutrient profiles.

Although it is recognised that the provision of food, particularly ready-made meals, help to ensure dietary adherence due to their convenience as well as promoting a more tightly controlled dietary intervention than if participants were preparing meals themselves, the MicroFit Study aims to assess adherence to the dietary prescription through the utilisation of the Easy Diet Diary app. The Easy Diet Diary is a free app available on smart phones and contains a database of commonly eaten foods for users to add to a diary at each eating occasion, without providing feedback about nutrition content. Dietary intake data from the app will be available to the researchers online and will be analysed for the energy and nutrient composition using FoodWorks (Xyris Software Pty Ltd, Australia).
Control group
Active

Outcomes
Primary outcome [1] 322672 0
Gut microbiota composition (shotgun metagenomic analysis), with bacteria being the targeted organisms.
Timepoint [1] 322672 0
Baseline (week 0) and endpoint (week 3)
Secondary outcome [1] 379260 0
Microbiota gene functional identification (shotgun metagenomics)
Timepoint [1] 379260 0
Baseline (week 0) and endpoint (week 3)
Secondary outcome [2] 379743 0
Anthropometry: body weight, height, and waist and hip circumference (weighing scales; stadiometer; and measuring tape, respectively)
Timepoint [2] 379743 0
Baseline (week 0) and endpoint (week 3)
Secondary outcome [3] 379747 0
Symptoms of depression, anxiety and stress (DASS-21 sub-scale and total scores)
Timepoint [3] 379747 0
Baseline (week 0) and endpoint (week 3)
Secondary outcome [4] 379748 0
Perceived well-being (WHO-5 Well-Being Index)
Timepoint [4] 379748 0
Baseline (week 0) and endpoint (week 3)
Secondary outcome [5] 379749 0
Sleep quality and duration (Athens Insomnia Scale (AIS)) - composite secondary outcome
Timepoint [5] 379749 0
Baseline (week 0) and endpoint (week 3)
Secondary outcome [6] 379750 0
Stool consistency (Bristol Stool Scale (BSS))
Timepoint [6] 379750 0
Baseline (week 0) and endpoint (week 3)
Secondary outcome [7] 379751 0
Gastrointestinal symptomology (Visual Analogue Scale for Irritable Bowel Syndrome (VAS-IBS))
Timepoint [7] 379751 0
Baseline (week 0) and endpoint (week 3)
Secondary outcome [8] 379752 0
Physical activity (International Physical Activity Questionnaire-Short Form (IPAQ-SF))
Timepoint [8] 379752 0
Baseline (week 0) and endpoint (week 3)
Secondary outcome [9] 379753 0
Habitual dietary intake (Dietary Questionnaire for Epidemiological Studies v3.2 (DQES v3.2))
Timepoint [9] 379753 0
Baseline (week 0)
Secondary outcome [10] 380265 0
Blood liver function biomarkers (fasted): alanine aminotransferase (ALT); gamma-glutamyl transpeptidase (GGT); alkaline phosphatase (ALP); aspartate aminotransferase (AST); total bilirubin; albumin; and, total protein (Australian Clinical Labs) - composite secondary outcome
Timepoint [10] 380265 0
Baseline (week 0) and endpoint (week 3)
Secondary outcome [11] 380266 0
Blood glucose (fasted) (Australian Clinical Labs)
Timepoint [11] 380266 0
Baseline (week 0) and endpoint (week 3)
Secondary outcome [12] 380267 0
Insulin (fasted) (Australian Clinical Labs)
Timepoint [12] 380267 0
Baseline (week 0) and endpoint (week 3)
Secondary outcome [13] 380268 0
Blood lipid levels (fasted): high-density lipoprotein cholesterol (HDL); low-density lipoprotein cholesterol (LDL); total cholesterol; and, triglycerides (Australian Clinical Labs) - composite secondary outcome
Timepoint [13] 380268 0
Baseline (week 0) and endpoint (week 3)
Secondary outcome [14] 380269 0
Leptin (fasted) (Australian Clinical Labs)
Timepoint [14] 380269 0
Baseline (week 0) and endpoint (week 3)
Secondary outcome [15] 380289 0
Inflammatory blood biomarkers (fasted): homocysteine; Interlukin-ßeta (IL-ß); Interlukin-6 (IL-6); Tumour Necrosis Factor-alpha (TNF-?); and C-reactive protein (CRP) (Australian Clinical Labs) - composite secondary outcome
Timepoint [15] 380289 0
Baseline (week 0) and endpoint (week 3)

Eligibility
Key inclusion criteria
• Female
• Aged between 30-65 years (at baseline)
• BMI between 30 kg.m-2 and 45 kg.m-2
• Willingness to commit to consuming only pre-made, pre-packaged food-based or supplement-based dietary products (in conjunction with Recommended Extras food) provided by the study for duration of study
• Available for study duration
• Ability to understand study directions and materials in English
• Access to internet and computer, smart phone or tablet
• Willingness to comply with all requirements and procedures of the study
• Agree not to enrol in another intervention clinical research trial while part of the study
Minimum age
30 Years
Maximum age
65 Years
Sex
Females
Can healthy volunteers participate?
No
Key exclusion criteria
• > 65 years and < 30 years
• BMI > 45 kg.m-2
• Current consumer of VLED weight loss consumables
• Food allergies (established medical diagnosis)
• Pregnant, planning to become pregnant during the trial period, or lactating
• Diagnosed with or commenced new treatment for, anxiety and/or depression, within 1 month prior to baseline
• Gastrointestinal (GI) diseases or past major GI surgery likely to interfere with study outcomes
• Type Two Diabetes Mellitus
• Porphyria
• Recent heart attack within the past six months
• Heart disease / failure or unstable angina
• Severe or advanced kidney / liver disease
• Any other condition the research team deem the prospective participant unfit to participate in the study
• Eating disorder(s) (established diagnosis)
• Other major medical conditions likely to have major systemic effects
• Regular use of the following:
• morphine/opioid-based medications
• recreational/illicit drugs
• Sodium-glucose co-transporter-2 (SGLT2) inhibitors (“gliflozins”)
• Antibiotic, prebiotic and/or probiotic use within 1 month prior to baseline
• Enrolment in another clinical trial within the past 3 months

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)
Allocation concealment involves central randomisation through a computer generated process.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Participants will be randomly assigned to receive either a food-based VLED (diet A) or supplement-based VLED (diet B) using permuted block randomisation. Numbers assigned to each group will be equal on a 1:1 ratio. The study statistician developed the computer-generated randomisation table utilising permuted block randomisation. A third party, independent of the research team, added this table to the study's software (REDCap), with REDCap's ability to generate a randomisation schedule.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
N/A
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
The MicroFit Study will recruit 48 participants that will be community-dwelling women with obesity (BMI between 30 and 45 kg.m-2). Power calculations are not yet routine in human microbiome studies. However, a sample size calculation was conducted based on a range of plausible scenarios of means and SDs for various alpha diversity metrics and relative abundance of microbial taxa at the phylum level. Data were taken from a study of similar design to inform sample size estimates. Our power calculation showed that The MicroFit Study has above 80% power to detect moderate to large effect sizes in alpha diversity and the relative abundance of phyla. Moreover, current microbiome studies in humans typically have a sample size of approximately 10-30 participants, thus the MicroFit Study will not be dissimilar.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
1/02/2021
Actual
4/05/2021
Date of last participant enrolment
Anticipated
1/12/2021
Actual
7/02/2022
Date of last data collection
Anticipated
31/12/2021
Actual
15/03/2022
Sample size
Target
48
Accrual to date
Final
47
Recruitment in Australia
Recruitment state(s)
VIC
Recruitment hospital [1] 15708 0
Barwon Health - Geelong Hospital campus - Geelong
Recruitment postcode(s) [1] 29129 0
3220 - Geelong

Funding & Sponsors
Funding source category [1] 304808 0
Commercial sector/Industry
Name [1] 304808 0
Be Fit Food
Country [1] 304808 0
Australia
Funding source category [2] 304809 0
University
Name [2] 304809 0
Deakin University Geelong Waterfront Campus
Country [2] 304809 0
Australia
Primary sponsor type
Hospital
Name
Barwon Health - University Hospital Geelong
Address
Bellerine St, Geelong VIC 3220
Country
Australia
Secondary sponsor category [1] 305131 0
University
Name [1] 305131 0
Deakin University Geelong Waterfront Campus
Address [1] 305131 0
1 Gheringhap St, Geelong VIC 3220
Country [1] 305131 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 305223 0
The Barwon Health Human Research Ethics Committee (BHREC)
Ethics committee address [1] 305223 0
PO Box 281
Geelong VIC 3220
Ethics committee country [1] 305223 0
Australia
Date submitted for ethics approval [1] 305223 0
24/07/2019
Approval date [1] 305223 0
18/11/2019
Ethics approval number [1] 305223 0
19/112
Ethics committee name [2] 305224 0
The Deakin University Human Research Ethics Committee (DUHREC)
Ethics committee address [2] 305224 0
Deakin Research Integrity
Deakin University
221 Burwood Hwy
Burwood, VIC 3125
Ethics committee country [2] 305224 0
Australia
Date submitted for ethics approval [2] 305224 0
06/12/2019
Approval date [2] 305224 0
13/12/2019
Ethics approval number [2] 305224 0
2019-466

Summary
Brief summary
The primary aim of this study is to investigate the possible differential effects of two VLEDs on gut microbiota composition and associated health in women with obesity. It is hypothesised that from baseline to endpoint, those allocated to the food-based VLED will have more diverse and abundant bacterial microbes compared to those in the supplement-based VLED. It is also hypothesised that those allocated to the food-based VLED will have more beneficial metabolic and mental health outcomes relative to the supplement-based VLED.
Trial website
https://foodandmoodcentre.com.au/projects/the-microfit-study-the-effect-of-very-low-energy-diets-for-weight-loss-on-gut-microbiota-composition-and-associated-health-in-women-with-obesity-a-randomised-controlled-trial/
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 99670 0
Prof Felice Jacka
Address 99670 0
Food and Mood Centre, Institute for Physical and Mental Health and Clinical Translation (IMPACT), Deakin University, Barwon Health, School of Medicine, PO Box 281, Geelong, Victoria, 3220
Country 99670 0
Australia
Phone 99670 0
+61 422194218
Fax 99670 0
Email 99670 0
[email protected]
Contact person for public queries
Name 99671 0
Ms Melissa Lane
Address 99671 0
Food and Mood Centre, Institute for Physical and Mental Health and Clinical Translation (IMPACT), Deakin University, Barwon Health, School of Medicine, PO Box 281, Geelong, Victoria, 3220
Country 99671 0
Australia
Phone 99671 0
+61 429691077
Fax 99671 0
Email 99671 0
[email protected]
Contact person for scientific queries
Name 99672 0
Prof Felice Jacka
Address 99672 0
Food and Mood Centre, Institute for Physical and Mental Health and Clinical Translation (IMPACT), Deakin University, Barwon Health, School of Medicine, PO Box 281, Geelong, Victoria, 3220
Country 99672 0
Australia
Phone 99672 0
+61 422194218
Fax 99672 0
Email 99672 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
Individual participant data underlying published results only.
When will data be available (start and end dates)?
Beginning 3 months and ending 5 years following main results publication.
Available to whom?
Case-by-case basis at the discretion of Primary Investigator, where a methodologically sound proposal and ethics application/amendment has been approved.
Available for what types of analyses?
Only to achieve the aims in the approved proposal.
How or where can data be obtained?
Access subject to approvals by Principal Investigator (Prof. Felice Jacka: [email protected])


What supporting documents are/will be available?

Current supporting documents:


Updated to:
Doc. No.TypeCitationLinkEmailOther DetailsAttachment
23744Study protocol    Access can be requested via the Health Data Austra... [More Details]
23745Data dictionary    Access can be requested via the Health Data Austra... [More Details]

Results publications and other study-related documents

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

Documents added automatically
No additional documents have been identified.