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Trial registered on ANZCTR


Registration number
ACTRN12609000178246
Ethics application status
Approved
Date submitted
23/03/2009
Date registered
17/04/2009
Date last updated
14/11/2018
Date data sharing statement initially provided
14/11/2018
Date results information initially provided
14/11/2018
Type of registration
Retrospectively registered

Titles & IDs
Public title
The acute effects of whey protein isolate on metabolic syndrome risk factors in overweight and obese individuals
Scientific title
The acute effects of whey protein isolate on metabolic syndrome risk factors in overweight and obese individuals
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Metabolic syndrome risk factors in overweight or obese individuals 4431 0
Condition category
Condition code
Diet and Nutrition 4698 4698 0 0
Obesity

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Randomised, single-blind, cross-over design study which invesigates the postprandial response to the acute ingestion of either a liquid preload of 50g of whey protein isolate, casein protein or glucose (control) mixed in 400 mls of water, over 3 visits, one day a week for 3 consecutive weeks.
Intervention code [1] 4176 0
Treatment: Other
Comparator / control treatment
Placebo - 50g glucose powder (same dose as whey & casein) mixed with 400ml water
Control group
Placebo

Outcomes
Primary outcome [1] 5566 0
Improved blood lipid and lipoprotein status as well as improved glucose and insulin sensitivity after the ingestion of the whey protein isolate
Timepoint [1] 5566 0
Fasting blood samples taken before liquid preload and then taken post meal (in minutes) - +15, 30, 60, 90, 120, 180, 240, 360.
Primary outcome [2] 5567 0
Improved blood pressure after ingestion of the whey protein isolate.Systolic blood pressure (SBP), diastolic blood pressure (DBP) and resting heart rate were measured on the left arm of participants with an automated sphygmomanometer (Dinamap ProCare). Subjects rested in a supine position before and during measurements.
Timepoint [2] 5567 0
Blood pressure taken before test meal & liquid preload, and then taken post meal (in minutes) - +30, 60, 90, 120, 180, 240, 360.
Primary outcome [3] 5568 0
Improved vascular endothelial function via Sphygmocor pulse wave analysis (PWA) after the ingestion of the whey protein isolate
Timepoint [3] 5568 0
PWA readings before test meal & liquid preload, then post meal (in minutes) - 30, 60, 90, 120, 180, 240, 360.
Secondary outcome [1] 9378 0
Greater satiety after ingesting the whey protein isolate relative to control.
Timepoint [1] 9378 0
Visual analogue scale (VAS) completed by subjects before test meal & liquid preload, and then post meal (in minutes) - 30, 60, 90, 120, 180, 240, 360.

Eligibility
Key inclusion criteria
Post-menopausal
Non-smoker
Body mass Index (BMI) between 25-35 kg/m2
Not taking regular medication
Not taking supplements, vitamins or herbal remedies
Weight stable
Less than 1-2 serves dairy per day
No major diseases/illness
Minimum age
45 Years
Maximum age
65 Years
Gender
Females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Smokers
Regular medications, especially those affecting blood lipids, blood pressure or thyroid
Premenopausal or perimenopausal
On a weight loss regime

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)
Numbered containers
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?



Intervention assignment
Crossover
Other design features
Three-way crossover design
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Completed
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)

Funding & Sponsors
Funding source category [1] 4620 0
Commercial sector/Industry
Name [1] 4620 0
Dairy Australia
Address [1] 4620 0
Locked Bag 104
Flinders Lane
Victoria 8009
Country [1] 4620 0
Australia
Primary sponsor type
Commercial sector/Industry
Name
Dairy Australia
Address
Locked Bag 104
Flinders Lane
Victoria 8009
Country
Australia
Secondary sponsor category [1] 4166 0
None
Name [1] 4166 0
Address [1] 4166 0
Country [1] 4166 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 6741 0
Curtin University Ethics Commitee
Ethics committee address [1] 6741 0
GPO BOX U1987
Perth WA 6845
Ethics committee country [1] 6741 0
Australia
Date submitted for ethics approval [1] 6741 0
11/11/2007
Approval date [1] 6741 0
11/12/2007
Ethics approval number [1] 6741 0
HR 131/2007

Summary
Brief summary
The prevalence of overweight/obesity is currently exploding with over 60% of Australian adults in this category, leading to a rapid increase in diabetes, hypertension, and cardiovascular disease (CVD). Increased dairy consumption has been demonstrated to significantly benefit weight loss. Initially, it was thought that diary calcium was the reason for these health benefits, but recent studies have shown that this is not the case. Attention is now focused to other dairy components, such as dairy proteins. Although there is no clinical evidence in humans to support this, exciting new research from animal studies have shown that dairy whey-protein isolate (WPI) can reduce body weight, lower plasma lipids, improve, blood pressure and insulin action. There is an urgent need to provide the scientific evidence to clarify whether the protein component is responsible for the observed association between dairy consumption and body weight. Therefore the aim of this study was to investigate whether acute ingestion of WPI affects postprandial lipemia, insulin sensitivity and endothelial function in overweight/obese adults.
Trial website
Trial related presentations / publications
Pal S, Ellis V, Ho S. Acute effects of whey protein isolate on cardiovascular risk factors in overweight, post-menopausal women. Atherosclerosis. 2010;212(1):339-44
Public notes

Contacts
Principal investigator
Name 29360 0
Address 29360 0
Country 29360 0
Phone 29360 0
Fax 29360 0
Email 29360 0
Contact person for public queries
Name 12607 0
Assoc Prof Sebely Pal
Address 12607 0
Curtin University
GPO Box U1987
Perth WA 6845
Country 12607 0
Australia
Phone 12607 0
+61 8 9266 4755
Fax 12607 0
Email 12607 0
s.pal@curtin.edu.au
Contact person for scientific queries
Name 3535 0
Assoc Prof Sebely Pal
Address 3535 0
Curtin University
GPO Box U1987
Perth WA 6845
Country 3535 0
Australia
Phone 3535 0
+61 8 9266 4755
Fax 3535 0
Email 3535 0
s.pal@curtin.edu.au

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No/undecided IPD sharing reason/comment
What supporting documents are/will be available?
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