Dose-dependent Effects of Blueberry Polyphenols on Endothelial Function in Healthy Individuals (BB2)

University of Reading

Status: Completed

Conditions: Endothelial Function

Treatments: Dietary Supplement: Freeze-dried blueberry powder dissolved in water; Dietary Supplement: Control

Study type: Interventional

Funder types: Other

Identifiers

NCT01829542

BB2UReading

Details and patient eligibility

About

The purpose of this study is to assess the impact of acute blueberry polyphenol intake on endothelial function of healthy volunteers. Specifically, the investigators plan to perform a randomised, double blind, cross-over human intervention trial using a blueberry drink to investigate the dose-dependent effects of blueberry polyphenols on blood vessel function using Flow mediated dilation (FMD) to measure endothelial function. The study will not only measure the acute effects of flavonoid ingestion on vascular reactivity but will also assess plasma polyphenol metabolite levels.

Enrollment: 11 patients

Sex: Male

Ages: 18 to 40 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Male
• 18-40 years
• Healthy
• signed consent form

Exclusion criteria

• Blood pressure > 140/90 mmHg
• Had suffered a myocardial infarction or stroke
• Suffers from any blood-clotting disorder
• Suffers from any metabolic disorders (e.g. diabetes or any other endocrine or liver diseases)
• Any dietary restrictions or on a weight reducing diet
• Allergies or intolerances to any foods
• Smoker
• Heavy drinker (>21 units per week)
• On any lipid-modifying medication
• On any blood pressure lowering medication
• On any medication affecting blood clotting
• Taking high dose fish oil supplements (greater then 1 g EPA and DHA per day) or high doses of antioxidant vitamins (greater then 800 μg vitamin A, 60 mg vitamin C, 10 mg vitamin E or 400 μg beta carotene)
• Taking probiotics, prebiotics, synbiotics, antibiotics or anti-inflammatory or blood lowering medication within a 2-month period prior to the study
• Planning on altering consumption of vitamin supplements/fish oil capsules during the course of the study
• Undertakes strenuous exercise > 4 times per week for > 1 hour per session
• Haemoglobin levels below reference range provided by the Royal Berkshire Hospital

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Quadruple Blind

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11 participants in 6 patient groups, including a placebo group

319 mg blueberry polyphenols

Active Comparator group

Description:

Freeze-dried blueberry powder dissolved in water

Treatment:

Dietary Supplement: Freeze-dried blueberry powder dissolved in water

639 mg blueberry polyphenols

Active Comparator group

Description:

Freeze-dried blueberry powder dissolved in water

Treatment:

Dietary Supplement: Freeze-dried blueberry powder dissolved in water

766 mg blueberry polyphenols

Active Comparator group

Description:

Freeze-dried blueberry powder dissolved in water

Treatment:

Dietary Supplement: Freeze-dried blueberry powder dissolved in water

1466 mg blueberry polyphenols

Active Comparator group

Description:

Freeze-dried blueberry powder dissolved in water

Treatment:

Dietary Supplement: Freeze-dried blueberry powder dissolved in water

1791 mg total blueberry polyphenols

Active Comparator group

Description:

Freeze-dried blueberry powder dissolved in water

Treatment:

Dietary Supplement: Freeze-dried blueberry powder dissolved in water

O mg blueberry polyphenols

Placebo Comparator group

Description:

Macro- and micronutrient matched control drink

Treatment:

Dietary Supplement: Control