Blood Pressure
Conditions
Keywords
Blood pressure, Flavanols, Cardiovascular disease
Brief summary
Fruit and vegetable rich diets are associated with a reduced risk of cardiovascular disease (CVD). The protective effect may be ascribed to compounds contained within these foods, called flavonoids. Flavanols (epicatechin and procyanidins) are a particular group of flavonoids and are found mostly in apples, berry fruits, dark chocolate, tea and red wine. There is evidence to suggest that ingestion of flavanol rich foods and beverages beneficially alter 'markers' of CVD risk (e.g. blood pressure). The aim of this study is to determine the acute and chronic effects of apple derived flavanols on some risk markers for CVD.
Detailed description
This study is a single arm randomized, 4-phase crossover design.
Interventions
DIETARY_SUPPLEMENTLow Epicatechin and procyanidin
70 mg epicatechin and 65 mg procyanidins once daily for 28 days
DIETARY_SUPPLEMENTHigh Epicatechin and procyanidin
140 mg epicatechin and 130 mg procyanidins once daily for 28 days
DIETARY_SUPPLEMENTHigh procyanidin
No epicatechin and 130 mg procyanidins once daily for 28 days
DIETARY_SUPPLEMENTPlacebo
Placebo control once daily for 28 days
Sponsors
Quadram Institute Bioscience
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
ALL
Age
50 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Men and women ≥ 50 years of age * Systolic blood pressure 130 - 159 mmHg
Exclusion criteria
* History of cardiovascular events such as stroke, myocardial infarction trans- ischaemic attacks or peripheral vascular disease * Kidney or liver disease/problems * Diabetes * Asthmatics (unless no medication taken for 1 year - occasional use will be assessed on an individual basis) * Prescribed anti-hypertensive medication * HRT (unless the participant has used the therapy for ≥ 6 months) * Lipid lowering therapies e.g. statins * Other medications that may affect any of the study outcome measures e.g. vasodilators (this will be assessed on a case by case basis) * Current smoker (or stopped for less than 3 months) * Throat surgery or neck injury * Allergy to apples * Consumption of fish oil supplements unless willing to discontinue them up for 4 weeks preceding the start of the study and for the duration of the study. (All other supplements will be assessed on a case by case basis) * Gastro-intestinal diseases (excluding hiatus hernia unless symptomatic or study intervention/procedure is contra-indicated). * Parallel participation in another research project which involves dietary intervention * Participation in another research project which has involved blood sampling within the last four months unless the total amount of combined blood from both studies does not exceed 470 ml. * Has donated or intends to donate blood within 16 weeks prior to or during the study period. * Depressed or elevated blood pressure measurements (\<90/50 or 95/55 if symptomatic or \>160/100 (mmHg)) during the course of the trial.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Changes in systolic blood pressure from baseline | Baseline, 2 hours and 4 weeks |
Secondary
| Measure | Time frame |
|---|---|
| Changes in plasma lipid profile from baseline | Baseline and 4 weeks |
| Change in plasma endothelin-1 from baseline | Baseline and 4 weeks |
| Changes in plasma nitric oxide metabolites from baseline | Baseline, 2 hours and 4 weeks |
| Changes in blood glucose from baseline | Baseline and 4 weeks |
| Changes in pulse wave velocity from baseline | Baseline, 2 hours and 4 weeks |
Countries
United Kingdom
Outcome results
None listed