Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12619000777190
Ethics application status
Approved
Date submitted
16/05/2019
Date registered
24/05/2019
Date last updated
21/07/2020
Date data sharing statement initially provided
24/05/2019
Date results information initially provided
21/07/2020
Type of registration
Prospectively registered

Titles & IDs
Public title
Effect of animal and plant proteins on glycaemic response to staple carbohydrates
Scientific title
Effect of lamb and plant protein (soy) on glycaemic response to New Zealand potatoes, pasta and rice. A randomised, repeated measures, human intervention study.
Secondary ID [1] 298238 0
Nil
Universal Trial Number (UTN)
U1111-1229-2668
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Diabetes 312841 0
Metabolic disorder 312842 0
Condition category
Condition code
Metabolic and Endocrine 311346 311346 0 0
Metabolic disorders
Metabolic and Endocrine 311347 311347 0 0
Diabetes

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The study is a randomized repeated measures design which means you will be asked to consume nine test foods, in random order, one per testing session as a single meal. Therefore you will need to be available for nine testing sessions.

The test meals will be as follows:
1. Boiled potato only (40g available carbohydrate)
2. Cooked pasta only (40 g available carbohydrate)
3. Cooked rice only (40 g available carbohydrate)
4. Boiled potato (40g available carbohydrate) + cooked mince lamb (84g – 1 serve)
5. Cooked pasta (40 g available carbohydrate) + cooked mince lamb (84g – 1 serve)
6. Cooked rice (40 g available carbohydrate) + cooked mince lamb (84g – 1 serve)
7. Boiled potato (40g available carbohydrate) + soy meat (cooked textured vegetable) protein (150g – 1 serve) (commercially sourced)
8. Cooked pasta only (40 g available carbohydrate) + soy meat (cooked textured vegetable protein) (150g – 1 serve) (commercially sourced)

9. Cooked rice only (40 g available carbohydrate) + soy meat (cooked textured vegetable protein) (150g – 1 serve) (commercially sourced)


An additional 200 ml of water will be consumed with all diets.
Individuals will be chosen to participate in the study if they are within the age bracket (18-65) and considered to be generally healthy. Health status will be determined initially by the use of a health questionnaire, which asks about your current and past health issues.
During the study, you will be required to refrain from eating after 9 pm and avoid any strenuous physical activity on the night preceding testing. We ask that you consume a similar evening meal before each of the 9 test days. In the morning you will be asked to rest for 15 mins before 2 baseline blood samples (by finger prick) are taken. You will then be given one of the nine test meals to consume within 10 mins and small blood samples will be taken at 0 (2 x, baseline), 15, 30, 45, 60, 90, 120 and 150 min after consuming the food. Blood sampling involves the use of a finger prick device which allows a small amount of blood to be massaged from the finger at each sampling time and used to monitor your blood glucose and insulin levels over the two and a half hours after consuming the food. During the 2.5 hours you will be able to continue with your normal work if it is not strenuous (e.g., office work), and drink a set amount of water if thirsty but consume no food until after the final blood test. Otherwise, you will be asked to rest and do some non-strenuous activity such as reading. You will be asked to fill out a visual analogue scale to assess your hunger at 0, 30, 60, 90, 120 and 150 mins. Lunch of your choice from the cafeteria options will be available free after the testing has been completed.
If you agree to take part in the study, we would like you to be available in the morning. Each visit will last a maximum of three hours.
There will be at least 48 hours 'wash out' period between treatments.
A trained research staff will administer the intervention including pricking finger.
Adherence to the intervention - During the study the participants will be required to refrain from eating after 9 pm, and avoid any strenuous physical activity on the night preceding testing. They will be asked to consume a similar evening meal before each of the 5 test days. The participants will be asked on the day of the test if they adhered to the restrictions. If the answer is 'no', then the participant will be asked come back for testing another day after having observed the restrictions.
Intervention code [1] 314495 0
Prevention
Intervention code [2] 314502 0
Lifestyle
Comparator / control treatment
Control - potatoes
All results will be compared with the results obtained for potatoes
Control group
Active

Outcomes
Primary outcome [1] 320088 0
To determine the effect of lamb and plant protein on the glycaemic responses to potato, pasta and rice.
Timepoint [1] 320088 0
Measure blood glucose concentrations at baseline (time 0 minute), 15, 30, 45, 60, 90, 120 and 150 minutes after a serving of the test meal (equivalent 40 g carbohydrate). Nine test sessions will be conducted with at least a 48-hour washout between sessions.
Primary timepoint is the baseline which is time zero (0 minute).
Secondary outcome [1] 370501 0
To determine the effect of lamb and plant protein on the insulin responses to potato, pasta and rice.
Timepoint [1] 370501 0
Measure insulin concentrations at 0, 15, 30, 45, 60, 90, 120 and 150 minutes after a serving of the test meal (equivalent 40 g carbohydrate). Nine test sessions will be conducted with at least a 48-hour washout between sessions.
Secondary outcome [2] 370502 0
Measure satiety with a visual analogue scale following consumption of the test meal
Timepoint [2] 370502 0
A visual analogue scale will be used to measure appetite over the 2.5 hours at 0, 30, 60, 120 and 150 mins. Nine test sessions will be conducted with at least a 48-hour washout between sessions.

Eligibility
Key inclusion criteria
• Age: Aged between 18 and 65.
• Sex: Male or female.
• Glucose tolerance: No history of diabetes or evidence of glucose intolerance in a preliminary screening test.
• Tolerant to potato, pasta, rice, meat and plant protein.
• Health: Healthy as gauged by self-assessment and result on the General Health Questionnaire.
• Agreement: Subject having given written informed consent to comply with the conditions of the trial.
Minimum age
18 Years
Maximum age
65 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
• Glucose intolerance: Any history of diabetes or evidence of glucose intolerance in a preliminary test less than 6.0mmol/l fasting glucose, International Diabetes Federation recommendation) and HbA1c greater than 40 mmol/mol
• Non-fasting: Having consumed anything apart from water in the twelve hours prior to the test.
• Vegetarian or vegan
• Allergic or intolerant to potatoes, pasta, rice, plant protein and meat
• Pregnant or breastfeeding.
• Long term chronic illnesses requiring treatment, such as cancer and cardiovascular disease.
• Gut conditions or drugs effecting gut transit time, such as irritable bowel syndrome, peptic ulcers and laxatives.

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)
Each participant will be assigned an identification number, including those who fail the screening procedure by central randomization by computer.

Participants who pass the screening procedure will be allocated numbers after the recruitment process is finished. Therefore, the recruiter was unaware of the treatment order for each individual at time of recruiting. Each participant receives all treatments in random order rather than being allocated to one group. Randomization of the samples and treatments will be completed by a statistician at Plant & Food Research using a computer.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The order of the diets and treatments for each subject (n=15) will be determined by computer randomisation of numbers
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Groups will be compared in terms of response amplitude, time 0 baseline and incremental area under the blood glucose response curve by comparison of treatments. A registered statistician at Plant and Foood Research will conduct the statistical analysis.

The participant numbers (n = 15) exceeds the minimum number (n=10) specified by the current ISO method (ISO 26642:2010) for determination of glycaemic index and is typical of studies involving comparisons of foods.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
15/07/2019
Actual
15/07/2019
Date of last participant enrolment
Anticipated
16/08/2019
Actual
16/08/2019
Date of last data collection
Anticipated
31/10/2019
Actual
13/12/2019
Sample size
Target
15
Accrual to date
Final
15
Recruitment outside Australia
Country [1] 21491 0
New Zealand
State/province [1] 21491 0
Manawatu

Funding & Sponsors
Funding source category [1] 302779 0
Government body
Name [1] 302779 0
New Zealand Institute for Plant and Food Research
Country [1] 302779 0
New Zealand
Primary sponsor type
Government body
Name
New Zealand Institute for Plant & Food Research
Address
Private Bag 11600, Palmerston North 4442, New Zealand
Country
New Zealand
Secondary sponsor category [1] 302723 0
None
Name [1] 302723 0
Address [1] 302723 0
Country [1] 302723 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 303375 0
Northern B Health and Disability Ethics Committee
Ethics committee address [1] 303375 0
Ministry of Health
133 Molesworth Street
PO Box 5013
Wellington
6011
Ethics committee country [1] 303375 0
New Zealand
Date submitted for ethics approval [1] 303375 0
15/03/2019
Approval date [1] 303375 0
17/04/2019
Ethics approval number [1] 303375 0
19/NTB/39

Summary
Brief summary
Potatoes are one of the most popular vegetables in the western diet. However, potatoes have a bad reputation as they generally induce a high blood glucose response after consumption. Our previous research measuring the glycaemic index (GI) of NZ potatoes gave an average GI of 86 (unpublished). However, in another trial, we found that potatoes were most satiating compared to pasta and rice when consumed on equal carbohydrate basis (Zhang et al. 2018). Yet another of our research projects has shown that blood glucose response to potatoes when co-consumed with salmon was significantly reduced (Ballance et al. 2018) compared with when the potato was consumed without salmon. Therefore, the aim of this trial to study the effect of lamb or plant protein (soy) on blood glucose and insulin responses to potatoes, rice and pasta to determine:
1. The relative glycaemic impact of potato when co-consumed with meat (protein) or plant protein (soy).
2. The glycaemic benefit of co-consuming protein with carbohydrate food.
3. The relative ability of meat and plant protein to reduce glycaemic response.
References:
Ballance S, Knutsen SH, Fosvold OW, Fernandez AS, Monro J 2018. Predicting mixed-meal measured glycaemic index in healthy subjects. European Journal of Nutrition.
Zhang Z, Venn BJ, Monro J, Mishra S 2018. Subjective Satiety Following Meals Incorporating Rice, Pasta and Potato. Nutrients 10(11).
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 93450 0
Dr John Monro
Address 93450 0
Plant and Food Research
Food Industry Science Centre
Private Bag 116000
Palmerston North 4474
Country 93450 0
New Zealand
Phone 93450 0
+64 63556137
Fax 93450 0
Email 93450 0
[email protected]
Contact person for public queries
Name 93451 0
Dr Suman Mishra
Address 93451 0
Plant and Food Research
Food Industry Science Centre
Private Bag 116000
Palmerston North 4474
Country 93451 0
New Zealand
Phone 93451 0
+64 63556146
Fax 93451 0
Email 93451 0
[email protected]
Contact person for scientific queries
Name 93452 0
Dr John Monro
Address 93452 0
Plant and Food Research
Food Industry Science Centre
Private Bag 116000
Palmerston North 4474
Country 93452 0
New Zealand
Phone 93452 0
+64 63556137
Fax 93452 0
Email 93452 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


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.