Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12622001321730
Ethics application status
Approved
Date submitted
30/09/2022
Date registered
12/10/2022
Date last updated
12/10/2022
Date data sharing statement initially provided
12/10/2022
Type of registration
Prospectively registered

Titles & IDs
Public title
Nutritional biomarkers comparing a healthy versus a typical Australian diet: a Feeding Study in Australian Adults.
Scientific title
Dietary metabolome profiles of a Healthy Australian Diet and a Typical Australian Diet: a randomized cross-over feeding study in Australian adults.
Secondary ID [1] 308031 0
None
Universal Trial Number (UTN)
Trial acronym
DQFS
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Diet-related cardiovascular disease 327711 0
Condition category
Condition code
Cardiovascular 324788 324788 0 0
Other cardiovascular diseases
Diet and Nutrition 324921 324921 0 0
Other diet and nutrition disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The Healthy Australian Diet (HAD) will provide foods to adequately meet the recommended servings of the 5 core food groups according to the current Australian Dietary Guidelines for adults e.g., 5.5 servings of grains/cereals; 5 servings of vegetables/legumes/beans; 2 servings of fruit; 3 servings of milk/yoghurt/cheese/alternatives and 2.5 servings of lean meats/alternatives.
The diet aims to meet the Acceptable Macronutrient Distribution Ranges (AMDR) e.g., 15-25% energy from protein, 45-65% energy from carbohydrates, 20-35% energy from fat; less than or equal to 10% energy from saturated fat and less than or equal to 1% energy from trans fat. Some emphasis will be given to specific nutrient targets such as fibre, free sugars, and sodium. Fruits and vegetables that are rich in beta-carotene (e.g., carrots, pumpkin, tomatoes, red capsicum, and sweet potato) will be emphasized during this dietary pattern. Characteristics of the food choices will reflect a high diet quality consistent with recommendations in the Australian Dietary Guidelines.

All meals and snacks are provided to participants for the duration of both 2-week diet intervention phases. This includes pre-prepared main meals (e.g., ready made fresh meals or frozen meals), fresh produce, cereals and snacks. Study investigators calorie-match the foods (to the participants baseline usual calorie intake) to be provided which are placed as a grocery order by the study investigators during the final appointment with the participants at the preceding phase. Participants collect the pre-ordered and pre-paid grocery items at their nearest allocated supermarket chain. The dietary intervention has been designed by and will be monitored by study coordinators who are also accredited practising dietitians. Participants are instructed to avoid consuming non-study foods, with usual beverage intake permitted accept for discretionary choice beverages.

Adherence to the dietary intervention will be assessed via the following tools:
• Completion of Participant Protocol Adherence Check List
• Three 24-hour food recalls per intervention phase as well as during run-in and washout to monitor dietary intake
• Daily record keeping of consumption of tea, coffee, and alcohol (using Easy Diet Diary app)
• Record keeping of any food consumed out of the home e.g., takeaway, restaurant / café foods and/or any non-study foods (using Easy Diet Diary app)
• Completion of Australian Eating Survey surveys at the end of each diet phase
• Attend two virtual study check-ins where investigators answer any questions to ensure participants adhere to protocol
• Measurement plasma metabolites for respective indicator foods during each diet phase will be used as dietary biomarkers to objectively assess compliance to diet protocol

After completion of each dietary intervention phase, participants undergo a 2-week washout period where they return to their usual food habits, eating their own food (i.e., no food is supplied during the washout period).

Upon enrolment, consent participants commence a 2-week run-in period prior to their first diet allocation. During the run-in period where they continue to consume their habitual diet (note, food is not supplied by study investigators for the run-in period). The run-in period includes collection of baseline data: social, medial, physical and demographic; bio-sampling (blood, plasma, urine, faecal), anthropometry, usual dietary intake and determine study adherence (i.e., attending appointments and completing various data collection measurements as outlined in the participant information sheet they would have consented to).
Intervention code [1] 324483 0
Lifestyle
Comparator / control treatment
Both diet phases are administered under the exact same procedures, with the same adherence and monitoring processed in place. Therefore, the only distinction is the characteristics of the diet / foods provided.

The Typical Australian Diet (TAD) will reflect the apparent consumption of Australians published by the Australian Bureau of Statistics (ABS). The ABS measured apparent consumption as the amount of food and non-alcoholic beverages purchased from food and retail sectors e.g., major supermarkets, smaller outlets, delis, fresh food markets, butchers etc from July 2020 to June 2021. Apparent consumption does not include foods purchased from restaurants, fast food outlets or foods sought by other means such as fishing. Apparent consumption does not necessarily represent total dietary consumption or consumption patterns of Australians, but it does provide insight into overall nutrition profile of foodstuffs sold in the food and retail sector in Australia. This data was used to inform the design of the TAD as it is the most recent reflection of the nutritional profile of Australians e.g., 15% energy from protein, 44% energy from carbohydrates, 39% energy from fat; 15% energy from saturated fat and 0.71% energy from trans fat. Fruits and vegetables that are low in beta-carotene (e.g., white potato, onion, cauliflower, pears) will be emphasised during this dietary pattern. Characteristics of the food choices will reflect a poor diet quality consistent with the apparent consumption of foods among Australians in 2020-21. Participants will be instructed to avoid consuming non-study foods, with usual beverage intake permitted and discretionary choice beverages encouraged.
Participants undergo the identical process of food provision as in the intervention phase i.e., all foods/meals provided for the 2-week duration of the comparator feeding phase with the diet calorie-matched for each participant by the study coordinators (accredited practising dietitians). The same adherence protocol checklist and items employed during the intervention phase are also employed during this diet phase.
Control group
Active

Outcomes
Primary outcome [1] 332616 0
Plasma metabolites (exploratory outcome)
Timepoint [1] 332616 0
Baseline (end of run-in phase), Week 4 (end diet phase 1), Week 6 (end of washout) and Week 8 (end of diet phase 2).
Primary outcome [2] 332617 0
Urinary metabolites (exploratory outcome)
Timepoint [2] 332617 0
Baseline (end of run-in phase), Week 4 (end diet phase 1), Week 6 (end of washout) and Week 8 (end of diet phase 2).
Secondary outcome [1] 414056 0
Fasting blood glucose
Timepoint [1] 414056 0
Baseline (end of run-in phase), Week 4 (end diet phase 1), Week 6 (end of washout) and Week 8 (end of diet phase 2).
Secondary outcome [2] 414057 0
Fasting lipid profile (total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, total choleserol:to:HDL cholesterol ratio) in blood.
Timepoint [2] 414057 0
Baseline (end of run-in phase), Week 4 (end diet phase 1), Week 6 (end of washout) and Week 8 (end of diet phase 2).
Secondary outcome [3] 414058 0
Genetic risk score quantified from blood samples which will have their DNA extracted to be genotyped
Timepoint [3] 414058 0
Baseline (end of run-in phase), Week 4 (end diet phase 1), Week 6 (end of washout) and Week 8 (end of diet phase 2).
Secondary outcome [4] 414059 0
Plasma fatty acids
Timepoint [4] 414059 0
Baseline (end of run-in phase), Week 4 (end diet phase 1), Week 6 (end of washout) and Week 8 (end of diet phase 2).
Secondary outcome [5] 414060 0
Plasma carotenoids
Timepoint [5] 414060 0
Baseline (end of run-in phase), Week 4 (end diet phase 1), Week 6 (end of washout) and Week 8 (end of diet phase 2).
Secondary outcome [6] 414061 0
Qualitative dietary intake (Australian Eating Survey)
Timepoint [6] 414061 0
Baseline (end of run-in phase), Week 4 (end diet phase 1), Week 6 (end of washout) and Week 8 (end of diet phase 2).
Secondary outcome [7] 414062 0
Quantitative dietary intake (24-hr recall)
Timepoint [7] 414062 0
Weekly.
Baseline (Week 1 & Week 2 - Run-in phase), Week 3 & 4 (diet phase 1), Week 5&6 (end of washout) and Week 7 & 8 (end of diet phase 2).
Secondary outcome [8] 414063 0
Appetite and hunger scale (Visual Analogue Scale, VAS)
Timepoint [8] 414063 0
Weekly.
Baseline (Week 1 & Week 2 - Run-in phase), Week 3 & 4 (diet phase 1), Week 5&6 (end of washout) and Week 7 & 8 (end of diet phase 2).
Secondary outcome [9] 414064 0
Physical activity (Active Australia Survey)
Timepoint [9] 414064 0
Baseline (Week 2, end of run-in phase), Week 4 (end diet phase 1), Week 6 (end of washout) and Week 8 (end of diet phase 2).
Secondary outcome [10] 414066 0
Faecal flora measured via faecal sample culture (exploratory outcome)
Timepoint [10] 414066 0
Baseline (Week 2, end of run-in phase), Week 4 (end diet phase 1), Week 6 (end of washout) and Week 8 (end of diet phase 2).
Secondary outcome [11] 414068 0
Body weight using bioelectrical impedance will be measured by study coordinators (research Dietitians) in weeks 2, 4, 6 and 8 and by participants at home using their own set of scales in weeks 3, 5 and 7.
Timepoint [11] 414068 0
Weekly.
Baseline (Week 1 & Week 2 - Run-in phase), Week 3 & 4 (diet phase 1), Week 5&6 (end of washout) and Week 7 & 8 (end of diet phase 2).
Secondary outcome [12] 414069 0
Fat mass using bioelectrical impedance will be measured by study coordinators (research Dietitians)
Timepoint [12] 414069 0
Baseline (Week 2, end of run-in phase), Week 4 (end diet phase 1), Week 6 (end of washout) and Week 8 (end of diet phase 2).
Secondary outcome [13] 414070 0
Waist circumference using a tensible tape measure
Timepoint [13] 414070 0
Baseline (Week 2, end of run-in phase), Week 4 (end diet phase 1), Week 6 (end of washout) and Week 8 (end of diet phase 2).
Secondary outcome [14] 414071 0
Blood pressure (Systolic/diastolic) using an automatic blood pressure monitor
Timepoint [14] 414071 0
Baseline (Week 2, end of run-in phase), Week 4 (end diet phase 1), Week 6 (end of washout) and Week 8 (end of diet phase 2).
Secondary outcome [15] 414072 0
Skin carotenoids will be measured using a CM700D spectrophotometer (Konica Minolta) with an 8-mm diameter aperture, 2-degree observer angle, and illuminant D65. Skin colour (CIE L*a*b* values, where positive L*, a* and b* values represent lightness, redness, and yellowness, respectively) will be recorded for each participant on the waist or arm and repeated 3 times at each site.
Timepoint [15] 414072 0
Baseline (Week 2, end of run-in phase), Week 4 (end diet phase 1), Week 6 (end of washout) and Week 8 (end of diet phase 2).
Secondary outcome [16] 414536 0
% body fat using bioelectrical impedance will be measured by study coordinators (research Dietitians)
Timepoint [16] 414536 0
Baseline (Week 2, end of run-in phase), Week 4 (end diet phase 1), Week 6 (end of washout) and Week 8 (end of diet phase 2).
Secondary outcome [17] 414537 0
Skeletal muscle mass using bioelectrical impedance will be measured by study coordinators (research Dietitians)
Timepoint [17] 414537 0
Baseline (Week 2, end of run-in phase), Week 4 (end diet phase 1), Week 6 (end of washout) and Week 8 (end of diet phase 2).
Secondary outcome [18] 414538 0
Fat free mass using bioelectrical impedance will be measured by study coordinators (research Dietitians)
Timepoint [18] 414538 0
Baseline (Week 2, end of run-in phase), Week 4 (end diet phase 1), Week 6 (end of washout) and Week 8 (end of diet phase 2).
Secondary outcome [19] 414559 0
Arterial stiffness measured using Cardioscope
Timepoint [19] 414559 0
Baseline (Week 2, end of run-in phase), Week 4 (end diet phase 1), Week 6 (end of washout) and Week 8 (end of diet phase 2).

Eligibility
Key inclusion criteria
• Healthy adults (aged 18 years and older)
• Currently taking no medications or are on stable medication therapy for the last 3 months
• Willing to adhere to strict diet protocol for 8 weeks
• Access to a smart phone or tablet with access to the internet
• In the Newcastle region for at least the entirety of the two feeding intervention periods
Minimum age
18 Years
Maximum age
70 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Volunteers will be excluded if they have/are:
• Food allergies or intolerances
• Uncontrolled hypertension as defined by the National Heart Foundation of Australia (systolic blood pressure greater than or equal to 180 and/or diastolic blood pressure greater than or equal to 110)
• Type 1 diabetes or insulin-dependent Type 2 diabetes
• Cancer receiving treatment
• Following strict diet regimen e.g., vegan, intermittent fasting
• Noncompliant during run in stage
• Individuals who have lost or gained greater than or equal to 5% body weight in the past 2 months
• History of gastric ulcers, gastrointestinal disorders including severe digestive disorders such as irritable bowel syndrome
• On medication known to influence study outcomes e.g. antibiotics, probiotics or prebiotics, hormone therapy, anti-inflammatory medications, corticosteroids, medications affecting metabolism
• Routinely taking any supplements known to influence the study outcomes e.g. fish oils
• On unstable medication regimens
• Currently participating in another research intervention trial involving dietary intervention and/or physical activity intervention
• Chronic or excessive alcohol consumption as per NHMRC Guidelines to Reduce Health Risks from Drinking Alcohol (greater than 10 standard drinks per week)
• Pregnant or breastfeeding

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation is not concealed.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Participants will be randomized to using simple randomisation using a randomisation table created by computer software (i.e. computerised sequence generation) available on REDCap.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Crossover
Other design features
This study is a cross-over study design, with a 2-week run-in period (usual diet) at the start, following by 2 weeks dietary intervention phase 1, 2 week washout period (usual diet), 2 week dietary intervention phase 2.
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Data will be evaluated by mixed model ANOVA with sequence and interaction between diet and start/end of treatment periods as fixed effects, and participants within sequence and visit as random effects. Least square means will be estimated for the start (HAD-week 0, TAD-week 0) and end values (HAD-week 2, TAD-week 2) for each diet period for outcomes of interest (e.g., dietary intake, cardiometabolic risk factors etc). Least square means and confidence intervals will be calculated for the differences between HAD/week 0, TAD/week 0, HAD/week 2 and TAD/week 2, as well as for the net difference between the diets, i.e. (HAD/week 2 - HAD/week 0) - (TAD/week 2 - TAD/week 0) for study outcomes.
Spearman correlation coefficients (rs) will be used to examine the relationship between the changes in the cardiometabolic-related biomarkers (and other health markers/outcomes) and the significantly differentiated metabolites.
To further examine the relationship between HAD and TAD dietary intervention periods and biological markers/metabolites statistical tests including Spearman correlation coefficients, PCA and PLS-DA plots, VIP/S plots and random-forest plots may be undertaken to identify candidate biomarkers. Linear mixed models or regression models accounting for covariates identified will be run to quantify the relationship between these biomarkers and dietary intakes.
Results will be analysed as both unadjusted and adjusted values to take into consideration potential confounders such as age, BMI, and gender. As this is an exploratory intervention adjustments will be limited to be conservative. However additional confounders identified may be included in these models as necessary.
Analyses will be conducted using StataIC 14 (Stata Statistical Release Software: Release 14. College Station, TX: StataCorp LP). A p < 0.05 will be considered statistically significant.

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
14/10/2022
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
40
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
NSW

Funding & Sponsors
Funding source category [1] 312292 0
Government body
Name [1] 312292 0
National Health and Medical Research Council
Country [1] 312292 0
Australia
Primary sponsor type
University
Name
University of Newcastle
Address
University of Newcastle
University Dr, Callaghan NSW 2308
Country
Australia
Secondary sponsor category [1] 313837 0
None
Name [1] 313837 0
Address [1] 313837 0
Country [1] 313837 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 311661 0
Hunter New England Human Research Ethics Committee (HNEHREC)
Ethics committee address [1] 311661 0
HNE Research Office
HMRI, Level 3 POD
Lot 1, Kookaburra Circuit
New Lambton Heights NSW 2305
Ethics committee country [1] 311661 0
Australia
Date submitted for ethics approval [1] 311661 0
12/08/2022
Approval date [1] 311661 0
26/09/2022
Ethics approval number [1] 311661 0
2022/ETH01649
Ethics committee name [2] 311701 0
University of Newcastle’s Human Research Ethics Committee (HREC)
Ethics committee address [2] 311701 0
University of Newcastle
University Drive, Callaghan 2308
NSW, Australia
Ethics committee country [2] 311701 0
Australia
Date submitted for ethics approval [2] 311701 0
28/09/2022
Approval date [2] 311701 0
Ethics approval number [2] 311701 0
2022/ETH01649

Summary
Brief summary
A randomized cross-over feeding study conducted in free-living healthy adults aged 18 years and older old recruited from the local Hunter region. Participants will be enrolled in an 8-week dietary intervention consisting of a 2-week run-in period (habitual/usual diet) followed by 2 x 2-week dietary intervention periods that include a 2-week washout between them. The 2-week diet periods will consist of a ‘Healthy Australian Diet’ that aligns with Australian recommendations and a ‘Typical Australian Diet’. These will be allocated in a randomized order. During the 2-week washout period the participant returns to their / usual diet). The entirety of the diet (i.e., 3 main meals and snacks per day) will be provided to participants during dietary period 1 and 2. Participants will supply their own meals and foods during the run-in and washout periods. Study participation involves completing self-administered questionnaires (e.g., food frequency, health. demographic, physical activity questionnaire); collection of biosamples (fasted blood sample, urine and faecal sample) and physical measurements such as blood pressure, arterial stiffness, anthropometry and body composition. Researchers hypothesise that distinct nutrition biomarkers will be detected that are representative of each diet phase.
Trial website
Trial related presentations / publications
Public notes
Additional eligibility note: Participants who have received at least three vaccinations against the COVID-19 are eligible to participate.

Contacts
Principal investigator
Name 121898 0
Prof Clare Collins
Address 121898 0
ATC 310
Building ATC Building
University of Newcastle, University Drive
Callaghan, NSW 2308
Australia
Country 121898 0
Australia
Phone 121898 0
+61 2 4921 5646
Fax 121898 0
+61 2 4921 7053
Email 121898 0
[email protected]
Contact person for public queries
Name 121899 0
Dr Jessica Ferguson
Address 121899 0
ATC Building Room 205, The University of Newcastle, University Drive, Callaghan, NSW 2308
Country 121899 0
Australia
Phone 121899 0
+61 2 4921 5646
Fax 121899 0
+61 2 49212084
Email 121899 0
[email protected]
Contact person for scientific queries
Name 121900 0
Prof Clare Collins
Address 121900 0
ATC 310
Building ATC Building
University of Newcastle, University Drive
Callaghan, NSW 2308
Australia
Country 121900 0
Australia
Phone 121900 0
+61 2 4921 5646
Fax 121900 0
+61 2 4921 7053
Email 121900 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
This is not apart of our current ethics approval.


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
EmbaseDietary metabolome profiles of a Healthy Australian Diet and a Typical Australian Diet: protocol for a randomised cross-over feeding study in Australian adults.2023https://dx.doi.org/10.1136/bmjopen-2023-073658
N.B. These documents automatically identified may not have been verified by the study sponsor.