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Trial registered on ANZCTR


Registration number
ACTRN12614000519651
Ethics application status
Approved
Date submitted
9/05/2014
Date registered
15/05/2014
Date last updated
21/07/2016
Type of registration
Prospectively registered

Titles & IDs
Public title
Effect of different types of food consumption on the incidence of type 2 diabetes in both normal weight and overweight/obese participants with no diabetes.
Scientific title
Effect of a healthy diet and an unhealthy diet on insulin sensitivity in both normal weight and overweight/obese participants with no diabetes: a randomised crossover study
Secondary ID [1] 284562 0
Nill
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Normal glucose levels and prediabetes such as IGT and IFG 291831 0
insulin resistance 291832 0
Overweight /obesity 296497 0
Diabetes 296498 0
Condition category
Condition code
Diet and Nutrition 292196 292196 0 0
Other diet and nutrition disorders
Metabolic and Endocrine 292238 292238 0 0
Diabetes

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This study is a randomized cross-over trial with two different diets: one is a dietary pattern with high red meat and processed meat and refined grains and the other with legumes, nuts, whole grains and dairy products. This study will run for at least 10 weeks and 2 days with 8 visits. The intervention will consist of two 4 week weight stable diet periods with a minimum of 2-week washout period on a usual diet in between.
Participants will be asked to fill out a 3-day weighed food record every 2 weeks and daily checklists with food consumed. Participants will be asked to follow specific instructions on diet.
The two diets will be designed for individuals depending on their weight and activity levels. The dietary design of this project has been virtually run by foodworks 7 based on Australian dietary habits.
The dietary cluster with red and processed meat and refined grains includes 200-300g red meat, more than 50g processed meat (ham, bacon and sausage) and 4-6 serves refined grains (bread, rice, noodle and pasta) based on volunteers’ weights. One to two serves vegetables/day, 1-2 serves fruits/day and a minimal amount of dairy products (e.g. 1-2 teaspoons of milk). Two hundred to three hundred gram of potatoes, 1 serve of jam or marmalade, 3-9 serves of oil or spread, and 3-4 serves of indulgence food (in place of refined grains or potato) were recommended for additional energy intake in accordance with volunteers’ weights.
In the dietary cluster high in nuts, legumes, whole grains and dairy products, participants will consume 4 serves of dairy products/day, 60-90 g unsalted nuts/day, 3-4 serves whole grains/day in the forms of breads, rice and pasta, 1-2serves fruits and 1-2 serves vegetables/day. 70-150 g chicken or fish (or other seafood) or 150-225 g cooked legumes based on the volunteers’ weight will be eaten alternatively each day. Two to seven serves of oil or spread and 1 serve of jam or marmalade were advised for additional energy intake in accordance with volunteers’ weights.
Participants will be provided with kitchen scales. Participants will be asked to submit a 3-day weighed food record and daily checklists at visit 2, 3, 6 and 7. Participants will be required to have a 12 hour fast before each visit. Weight measurement and blood sampling will be performed during the course of this study.
Blood samplings by MTT (meal tolerance test) and LDIGIT (low dose insulin and glucose infusion test) will be performed at the end of each diet.
In terms of MTT, participants will be asked to consume a sandwich within 10 min. Blood samples will be taken at -5, 0, 10, 20, 30, 40, 50, 60, 75, 90, 120, 150, and 180 min.
On the other day, LDIGIT will be administered over 150 min after a 12h overnight fast. 19 blood samples will be collected over 150 min. Blood samples will be retained for measurements of insulin, C-peptide and glucose.
Intervention code [1] 289334 0
Other interventions
Comparator / control treatment
Diet high in red meat, processed meat and refined grains is comparator.
Control group
Active

Outcomes
Primary outcome [1] 292068 0
insulin sensitivity using LDIGIT (low dose insulin and glucose infusion test)
Timepoint [1] 292068 0
Timepoint 1: after first 4- week dietary intervention; Timepoint 2: after second 4- week dietary intervention
Secondary outcome [1] 308128 0
Lipid profiles will be measured by Konelab.


Timepoint [1] 308128 0
It is a single timepoint at 10 weeks and 2days.
Secondary outcome [2] 325527 0
We will measure CRP by Konelab
Timepoint [2] 325527 0
It is a single timepoint at 10 weeks and 2 days.

Eligibility
Key inclusion criteria
1. People in BMI ranges of 18.50 to 45
2. Aged over 18 years
3. Normal glucose tolerance or impaired glucose tolerance
Minimum age
18 Years
Maximum age
75 Years
Gender
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
1.Diagnosed diabetes
2.Drugs that influence glucose metabolism (e.g. Metformin)
3.Pregnant or breastfeeding
4.History of metabolic illness such as kidney or liver diseases

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)
Flyers will be posted around the Universtiy and on the public boards.Contact information will be provided on the flyers, so participants will call or email the researchers if they are interested in learning more. Anyone that contacts the researchers about the study will be given an information sheet outlining the project and if they are interested in participating, they will be screened to see if they meet the inclusion or exclusion criteria.
Allocation is not concealed.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Randomisation was performed via an online random number generator (www.randomization.com) by a researcher who was not involved in this study.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?



The people analysing the results/data
Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis
25 participants in each group would give 80% power (P<0.05) to assess insulin sensitivity for overweight participants with either NGT or IGT using LDIGIT (Mean= 11.8 and 8.9; SD=5.19). 30 participants in each group will be recruited considering a 20% dropout rate.

reference
Piatti, P., et al., The continuous low dose insulin and glucose infusion test: a simplified and accurate method for the evaluation of insulin sensitivity and insulin secretion in population studies. The Journal of clinical endocrinology and metabolism, 1995. 80(1): p. 34-40.

Recruitment
Recruitment status
Active, not 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)
SA

Funding & Sponsors
Funding source category [1] 289191 0
University
Name [1] 289191 0
University of South Austraila
Address [1] 289191 0
University of South Australia
City East Campus
GPO Box 2471
Adelaide SA 5001
Country [1] 289191 0
Australia
Primary sponsor type
University
Name
University of south Australia
Address
University of South Australia
City East Campus
GPO Box 2471
Adelaide SA 5001
Country
Australia
Secondary sponsor category [1] 287861 0
None
Name [1] 287861 0
Address [1] 287861 0
Country [1] 287861 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 290976 0
Uni SA HREC (Human Research Ethics Committee)
Ethics committee address [1] 290976 0
Research and Innovation Services
University of South Australia
General Purpose Building
Mawson Lakes Campus
Mawson Lakes Boulevard
Mawson Lakes, SA, 5095
Australia

Ethics committee country [1] 290976 0
Australia
Date submitted for ethics approval [1] 290976 0
08/04/2014
Approval date [1] 290976 0
16/05/2014
Ethics approval number [1] 290976 0
0000032778

Summary
Brief summary
1. Hypothesis
We hypothesise that red and processed meat and refined grains negatively affect insulin sensitivity or insulin secretion, compared with dairy products, legumes, nuts and whole grains.
2.Aims
If a dietary pattern rich in nuts, legumes, whole grains and dairy products improves insulin sensitivity, this study will strongly support the recommendation of this diet for people with no diabetes.
If a dietary pattern high in red, processed meat and refined grains affects negatively insulin sensitivity, this outcome will provide a convincing rationale in reducing the amount of intake of red, processed meat and refined grains for those with insulin resistance.
This study will provide clarification on dietary influences on insulin sensitivity and contribute to lowering risks of developing type 2 diabetes by changing the dietary patterns.
3. Primary and secondary endpoints
The primary endpoint of this study is to assess insulin sensitivity and the secondary endpoint is to analyse the biomarkers of insulin resistance.
Trial website
Trial related presentations / publications
Public notes
Attachments [1] 52 52 0 0

Contacts
Principal investigator
Name 48186 0
Mrs Yoona Kim
Address 48186 0
School of Pharmacy and Medical Sciences
Division of Health Sciences
University of South Australia
City East Campus, North Terrace
Adelaide SA 5000
Country 48186 0
Australia
Phone 48186 0
+61 8 8302 1025
Fax 48186 0
Email 48186 0
kimyy031@mymail.unisa.edu.au
Contact person for public queries
Name 48187 0
Mrs Yoona Kim
Address 48187 0
School of Pharmacy and Medical Sciences
Division of Health Sciences
University of South Australia
City East Campus, North Terrace
Adelaide SA 5000
Country 48187 0
Australia
Phone 48187 0
+61 8 8302 1025
Fax 48187 0
Email 48187 0
kimyy031@mymail.unisa.edu.au
Contact person for scientific queries
Name 48188 0
Prof Peter clifton
Address 48188 0
School of Pharmacy and Medical Sciences
Division of Health Sciences
University of South Australia
City East Campus, North Terrace
Adelaide SA 5000
Country 48188 0
Australia
Phone 48188 0
+61 8 8302 1357
Fax 48188 0
Email 48188 0
Peter.Clifton@unisa.edu.au

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary