Effects of Dietary Nitrate From Vegetable/Fruit Juice on Cerebral Blood Flow Parameters

Study Overview
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Brief Summary
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Nitrate provides the body with an alternative source of Nitric Oxide which plays a large role in promoting blood flow and reducing blood pressure. Nitrate supplementation with vegetable/fruit juice has recently been shown to reduce blood pressure and reduce energy expenditure during low intensity exercise. Such findings combined with the previously known biological effects of nitric oxide would suggest that nitrate supplementation would also impact on blood flow. The aim of this study is to examine the effects of dietary nitrate supplementation via vegetable/fruit juice drink on cerebral (brain) blood flow (using Near Infrared Spectroscopy).

Official Title
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Effects of Dietary Nitrate From Vegetable/Fruit Juice on Cerebral Blood Flow Parameters

Conditions
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Cerebrovascular Circulation, Cognitive Impairment

Intervention / Treatment
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* Dietary Supplement: Vegetable/fruit juice
* Dietary Supplement: Placebo juice


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: healthy young (18-35 years) male and female adults, not vulnerable. Exclusion Criteria: smoke or consume any tobacco products (even occasionally) not proficient in English pregnant (or are seeking to become) currently taking recreational, over the counter/prescription medication (excluding the contraceptive pill), and/or dietary/herbal supplements. any food allergies or sensitivities that are relevant to the study history of/current head trauma, learning difficulties, ADHD, dyslexia, migraines or any gastric problems.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 35 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Vegetable/ Fruit juice<br>450ml active product, 45 ml no added sugar squash (for flavour) | Dietary Supplement: Vegetable/fruit juice<br>* 450ml active juice, 45ml no added sugar fruit squash (for flavour)<br>|
| Placebo Comparator: Placebo juice<br> | Dietary Supplement: Placebo juice<br>* 50 ml No Added Sugar fruit squash, 45 ml Pressed Apple Juice, 405ml with water.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from baseline cerebral blood flow | Near infrared spectroscopy monitoring of cerebral blood flow in the frontal cortex during demanding tasks. Monitored from baseline, through 90 minutes of drink absorption and 60 minutes of cognitive task performance. | From baseline to 2.5 hours post-dose | 
| Change from baseline cognitive function | Performance of the cognitive demand battery (CDB), which assesses aspects of psychomotor speed, working memory and executive function. The CDB involves 6 repetitions of the following tasks: serial three subtractions (2 mins); serial seven subtractions (2 mins); Rapid Visual Information Processing (5 mins) and a subjective rating of mental fatigue | 90 minutes post-dose | 
| Change from baseline mood | Bond-Lader visual analogue mood scales assessing the mood factors 'alert'; 'calm'; and 'content' | 2.5 hours post-dose | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from baseline blood pressure, heart rate and venous nitrate and nitrite levels | Diastolic and systolic blood pressure and heart rate monitored after completion of cognitive tasks to assess peripheral blood flow effects. Plasma nitrate and nitrite levels assessed at 2.5 hours post-dose. | 2.5 hours post-dose |