Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12625001026415
Ethics application status
Approved
Date submitted
3/09/2025
Date registered
17/09/2025
Date last updated
17/09/2025
Date data sharing statement initially provided
17/09/2025
Type of registration
Prospectively registered

Titles & IDs
Public title
Feasibility of a food-based very-low-energy diet (VLED) in adults with obesity
Scientific title
A single-arm feasibility study of a food-based very-low energy diet (VLED) in adults with obesity
Secondary ID [1] 313595 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Obesity 335943 0
Condition category
Condition code
Diet and Nutrition 332532 332532 0 0
Obesity

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This single-centre, open-label study that explores the feasibility of a food-based very-low-energy diet (VLED) for adults with obesity. Participants will follow a balanced and nutritionally adequate, food-based VLED (<800 kcal/day) for 8 weeks. Participants will procure and prepare their own food during the intervention. Participants will be provided with written resources such as meal plan templates and food lists, which have been designed specifically for this study.

To ensure participant understands the dietary instructions and capable of making appropriate and realistic food choices, a sample meal plan will be co-created with the participant during the initial visit. Participants with specific dietary preferences, allergies and intolerances will be supported to identify suitable alternatives to meet individual needs, if specific needs extend the scope of the available resources.

Fortnightly dietitian-led visits will monitor feasibility outcomes including self-reported acceptability of the diet, dietary adherence, weight, waist and hip circumferences, body composition, blood pressure, and adverse effects. Individualised dietary advice, which account for individual dietary preferences and food allergies/intolerances, will be also provided by the study dietitian as needed at these visits. Blood and urine samples will be taken at baseline and week 8. During the final visit in week 8, participants will be asked to participate in an audio-recorded semi-structured interview regarding their perceptions and experiences of the intervention.

Duration of initial (baseline) visit is 1 hour. Follow up visits (week 2, 4, 6) 30 minutes. Final (week 8) visit including semi-structured interview 1.5 hours, of which the interview is 30 minutes.
Intervention code [1] 330085 0
Treatment: Other
Intervention code [2] 330086 0
Lifestyle
Comparator / control treatment
None
Control group
Uncontrolled

Outcomes
Primary outcome [1] 340054 0
Acceptability
Timepoint [1] 340054 0
Week 8 post intervention commencement
Primary outcome [2] 342652 0
Adherence
Timepoint [2] 342652 0
Week 8 post intervention commencement
Secondary outcome [1] 442480 0
Engagement
Timepoint [1] 442480 0
Week 8 post intervention commencement
Secondary outcome [2] 442481 0
Recruitment
Timepoint [2] 442481 0
Week 8 post intervention commencement
Secondary outcome [3] 442487 0
Retention
Timepoint [3] 442487 0
Week of last contactable date
Secondary outcome [4] 443311 0
body weight
Timepoint [4] 443311 0
Baseline and week 2, week 4, week 6, week 8 post intervention commencement
Secondary outcome [5] 443312 0
body mass index (BMI)
Timepoint [5] 443312 0
Baseline and week 2, week 4, week 6, week 8 post intervention commencement
Secondary outcome [6] 443313 0
% fat mass
Timepoint [6] 443313 0
Baseline and week 2, week 4, week 6, week 8 post intervention commencement
Secondary outcome [7] 443314 0
waist circumference
Timepoint [7] 443314 0
Baseline and week 2, week 4, week 6, week 8 post intervention commencement
Secondary outcome [8] 443315 0
blood pressure (systolic and diastolic)
Timepoint [8] 443315 0
Baseline and week 2, week 4, week 6, week 8 post intervention commencement
Secondary outcome [9] 443316 0
glucose
Timepoint [9] 443316 0
Baseline, week 8 post intervention commencement
Secondary outcome [10] 443317 0
calcium
Timepoint [10] 443317 0
Baseline, week 8 post intervention commencement
Secondary outcome [11] 451702 0
lipid profile (total cholesterol, triglycerides, HDL, LDL)
Timepoint [11] 451702 0
Baseline, week 8 post intervention commencement
Secondary outcome [12] 451703 0
iron studies (serum iron, ferritin, transferrin saturation)
Timepoint [12] 451703 0
baseline, week 8
Secondary outcome [13] 451704 0
serum zinc
Timepoint [13] 451704 0
Baseline, week 8 post intervention commencement
Secondary outcome [14] 451705 0
serum selenium
Timepoint [14] 451705 0
Baseline, week 8 post intervention commencement
Secondary outcome [15] 451706 0
iodine
Timepoint [15] 451706 0
Baseline, week 8 post intervention commencement
Secondary outcome [16] 451707 0
Dietary intake (energy, dietary fibre, macronutrients, micronutrients)
Timepoint [16] 451707 0
Baseline and week 2, week 4, week 6, week 8 post intervention commencement
Secondary outcome [17] 452047 0
hip circumference
Timepoint [17] 452047 0
Baseline and week 2, week 4, week 6, week 8 post intervention commencement
Secondary outcome [18] 452048 0
Magnesium
Timepoint [18] 452048 0
Baseline, week 8 post intervention commencement
Secondary outcome [19] 452049 0
Phosphate
Timepoint [19] 452049 0
Baseline, week 8 post intervention commencement
Secondary outcome [20] 452050 0
% fat-free mass
Timepoint [20] 452050 0
Baseline and week 2, week 4, week 6, week 8 post intervention commencement

Eligibility
Key inclusion criteria
Adults aged between 18 – 65 years and
BMI greater than or equal to 30 kg/metres squared or BMI greater than 27 kg/metres squared with 1 weight-related medical condition
Minimum age
18 Years
Maximum age
65 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Contraindications to VLED, including:
1. Lactating, pregnant or of childbearing potential who are not willing to avoid becoming
pregnant during the intervention
2. Myocardial infarction, cerebrovascular event or unstable angina within last 3 months
3. Porphyria
4. Unstable psychiatric conditions

Study design
Purpose of the study
Treatment
Allocation to intervention
Non-randomised 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
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Single group
Other design features
Phase
Not Applicable
Type of endpoint/s
Statistical methods / analysis
The primary and secondary outcome measures of feasibility (acceptability, adherence,
engagement, recruitment, retention) will be summarised descriptively for all participants.

Descriptive summary statistics (e.g. means, proportions, standard deviations or 95%
confidence intervals to describe uncertainty) will be used to describe data at baseline and
changes from baseline and week 8.

Qualitative data from semi-structured interviews will be analysed using thematic analysis and
reported descriptively.

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
1/10/2025
Actual
Date of last participant enrolment
Anticipated
1/03/2026
Actual
Date of last data collection
Anticipated
1/05/2026
Actual
Sample size
Target
10
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
VIC

Funding & Sponsors
Funding source category [1] 317961 0
University
Name [1] 317961 0
University of Melbourne
Country [1] 317961 0
Australia
Primary sponsor type
University
Name
University of Melbourne
Address
Country
Australia
Secondary sponsor category [1] 322470 0
None
Name [1] 322470 0
Address [1] 322470 0
Country [1] 322470 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 316633 0
University of Melbourne Central Human Research Ethics Committee
Ethics committee address [1] 316633 0
Ethics committee country [1] 316633 0
Australia
Date submitted for ethics approval [1] 316633 0
01/02/2025
Approval date [1] 316633 0
25/06/2025
Ethics approval number [1] 316633 0
2025-31540-67275-3

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 138478 0
A/Prof Priya Sumithran
Address 138478 0
School of Translational Medicine, Monash University Level 6, 99 Commercial Rd Melbourne VIC 3004 Australia
Country 138478 0
Australia
Phone 138478 0
+61 3 9903 8939
Fax 138478 0
Email 138478 0
[email protected]
Contact person for public queries
Name 138479 0
Shirley Poon
Address 138479 0
The University of Melbourne, Food and Nutrition Building (194), Room 233, Royal Parade, Victoria 3010 Australia
Country 138479 0
Australia
Phone 138479 0
+61 3 8344 0519
Fax 138479 0
Email 138479 0
[email protected]
Contact person for scientific queries
Name 138480 0
Priya Sumithran
Address 138480 0
School of Translational Medicine, Monash University Level 6, 99 Commercial Rd Melbourne VIC 3004 Australia
Country 138480 0
Australia
Phone 138480 0
+61 3 9903 8939
Fax 138480 0
Email 138480 0
[email protected]

Data sharing statement
Will the study consider sharing individual participant data?
No


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
No additional documents have been identified.