Investigating the Acute and Chronic Effects of Dietary Proteins on Markers of Vascular Function, Ambulatory Blood Pressure, Insulin Resistance and Lipid Metabolism.
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- University of Reading
- Enrollment
- 38
- Locations
- 2
- Primary Endpoint
- Change in 24-h ambulatory blood pressure
Study Overview
Brief Summary
Epidemiological studies demonstrated an inverse associations between cardiovascular events and milk and dairy product consumption. Evidence from human intervention studies suggests that both whey and casein may be effective in blood pressure-lowering, however there is limited data on the impact of milk proteins on vascular function. This research aims to compare the potential acute and chronic impacts of the two main milk proteins (whey and casein) with maltodextrin on blood pressure and vascular function. Furthermore, the effects of these proteins on the markers of insulin resistance, lipid metabolism and inflammatory status will also be investigated in 'at-risk' individuals.
This research includes both an acute and chronic intervention study which have been independently powered on the appropriate outcome measures. This has generated different sample size requirements for the two studies (Actual participants on the acute study: n=27, and on the chronic study: n=38).
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Crossover
- Primary Purpose
- Prevention
- Masking
- Triple (Participant, Investigator, Outcomes Assessor)
Eligibility Criteria
- Ages
- 30 Years to 77 Years (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •A signed consent form
- •Blood pressure: 120/80-159/99
- •Age: 30-77 years
- •BMI 20-40 kg/m2
- •Glucose <7 mmol/l (Not diagnosed with diabetes)
- •Chol <8 mmol/l
- •TAG <4 mmol/l
- •Normal liver and kidney function
- •Haemoglobin (>110 g/dl women; 140g/dl men)
Exclusion Criteria
- •Milk allergy, lactose allergy
- •Coeliac disease
- •Renal, gastrointestinal, respiratory, endocrine, liver disease or cancer
- •Surgery in the previous 6 months
- •Secondary hypertension
- •Excess alcohol consumption (drinking >28 unit/wk man; >21 unit/wk women)
- •Taking nutritional supplementation (e.g. fish oil, proteins)
Outcomes
Primary Outcomes
Change in 24-h ambulatory blood pressure
Time Frame: Chronic study: Baseline and week 8 assessments for the three dietary intervention arms, Acute study: automated ambulatory blood monitor measures every 15 minutes for 3 hours after both meals, then every 30 minutes for day
Secondary Outcomes
- Changes in vascular reactivity measured by flow-mediated dilation (FMD)(Chronic study: Baseline and week 8 assessments for the two dietary intervention arms, Acute study: determined at 0 (fasted), 180, 300, 420 min)
- Changes in plasma lipids(Chronic study: Baseline and week 8 assessments for the two dietary intervention arms, Acute study: fasted and postprandial)
- Changes in inflammatory markers(Chronic study: Baseline and week 8 assessments for the two dietary intervention arms, Acute study: fasted and postprandial)
- Changes in arterial stiffness measured by pulse wave analysis (PWA)(Chronic study: Baseline and week 8 assessments for the two dietary intervention arms, Acute study: determined at 0 (fasted), 180, 300, 420 min)
- Changes in arterial stiffness measured by digital volume pulse (DVP)(Chronic study: Baseline and week 8 assessments for the two dietary intervention arms, Acute study: determined at 0 (fasted), 180, 300, 420 min)
- Changes in markers of insulin resistance(Chronic study: Baseline and week 8 assessments for the two dietary intervention arms, Acute study: fasted and postprandial)
Investigators
Julie Lovegrove
Professor
University of Reading