Tea and Forearm Blood Flow

Unilever

Status: Completed

Conditions: Vascular Function

Treatments: Other: Placebo; Other: Tea

Study type: Interventional

Funder types: Other; Industry

Identifiers

NCT02328339

REF-BEV-1797

Details and patient eligibility

About

The study will explore the benefit of tea for microcirculation. Subjects will consume tea ar a placebo matched for taste and appearance in a blinded cross over design.

Full description

Epidemiological studies indicate that regular consumption of black tea reduces the risk of cardiovascular diseases. Tea consumption can result in improvements in endothelial function of conduit arteries as measured by flow mediated dilation.

Less is known however about its effects in other vascular beds. The study will test the hypothesis that tea affects endothelial function in the muscle microcirculation. This will be done by assessment of forearm blood flow using venous occlusion plethysmography after consumption of black tea against or placebo in a randomised, full cross-over study in 20 healthy middle-aged to elderly subjects

Enrollment: 20 patients

Sex: All

Ages: 45 to 75 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Males and post menopausal (> 1 years) females
• Aged ≥ 45 and ≤ 75 years
• Body mass index (BMI) of ≥ 18.0 and ≤ 35.0 kg/m2
• Judged to be in good health on the basis of medical history, physical examination and routine laboratory tests (total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides, glucose, highly sensitive C-reactive protein).
• Normal blood coagulation as assessed by routine lab tests

Exclusion criteria

• Strenuous exercise > 2 hours per week. Strenuous exercise is defined as exercise which induces sweating and causes sufficient breathlessness to limit conversation
• Current smoker or has stopped smoking less than 6 months before start of study
• Self reported alcohol intake of > 21 units/week)
• Established cardiovascular disease or clinically significant arrhythmia
• Diabetes mellitus
• Blood pressure > 160/100 mmHg
• Taking medication that might affect endothelial function (as judged by the PI)

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Quadruple Blind

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20 participants in 2 patient groups, including a placebo group

Black tea

Experimental group

Description:

Approximately 400 mg total polyphenols in 240 ml hot water (loading dose; 2 hours before the start of measurements; t=0) and 130 mg total polyphenols in 120 ml hot water (maintenance dose just before start of the measurements; t=120 min)

Treatment:

Other: Tea

Placebo

Placebo Comparator group

Description:

Caramel colour, maltodextrin and tea flavour in 240 ml hot water (2 hours before the start of measurements; t=0) and 120 ml hot water (maintenance dose just before start of the measurements; t=120 min)

Treatment:

Other: Placebo