Background: Increased cerebral vaso-dilation during cognitive demand is hypothesised to improve cognitive performance due to an improved micronutrient status. Despite previous research demonstrating that oral resveratrol can modulate cerebral haemodynamics, this has not translated into expected improvements to cognitive performance in young, healthy populations. As the brain is the most metabolic organ in the body, even subtle changes to fuel utilization and overall energy expenditure are detectable during cognitive demand. The measurement of both overall energy expenditure and fuel utilization may provide further insight to the effects of resveratrol and whether oral supplementation of this polyphenol can provide clear, cognitive benefits in a young, healthy sample.

Objectives: The current study investigated the metabolic consequences of resveratrol on whole body metabolism and fuel oxidisation during cognitive performance.

Methods: This repeated measures, double blind, placebo controlled, balanced design required participants (N=24 for metabolic activity & N=26 for cognitive outcomes) to complete a serial subtraction demand battery at baseline, 45 minutes, 2 and 3 hours following 500 mg, 250 mg trans-resveratrol or inert placebo, on three separate occasions whilst connected to an on-line gas analysis system.

Inclusion Criteria:

• Participants who were able to give informed consent.
• Those who didn't meet any of the exclusion criteria.
• Those who took hormonal contraception (e.g. the pill, coil, implant, etc.) were still allowed to participate in the current study.

Exclusion Criteria:

• Participants who smoke.
• Participants below the age of 18 years or above 35 years at the time of giving consent to in role in the current study.
• Participants with Body Mass Index outside the range of 18-35 kg/m2.
• Participants with blood pressure greater than 140/90 HH/mg.
• Participants with a history of neurological, vascular or psychiatric illness (excluding depressive illness and anxiety).
• Participants with a current diagnosis of depression and / or anxiety.
• Participants with learning difficulties: dyslexia, dyscalculia or colour blindness.
• Participants with a visual impairment that cannot be corrected with glasses or contact lenses.
• Participants with frequent migraines that require medication (more than or equal to 1 per month).
• Participants with disorders of the blood.
• Participants with a heart disorder.
• Participants with diabetes.
• Participants with a respiratory disorder that requires regular medication (Note: asthma sufferers who only take their medication occasionally/as required were eligible for this study).
• Participants currently taking any prescription medications.
• Participants who have habitually used dietary supplements within the last month (defined as more than 3 consecutive days or 4 days in total).
• Participants with any food intolerances/sensitivities.
• Participants with a history of renal or hepatic disease, or other severe diseases of the gastrointestinal tract (e.g., iron accumulation, iron utilization disorders, hypercalcaemia, hypercalciuria), that are likely to interfere with metabolism/absorption/secretion of the product under investigation.
• Female participants who are currently pregnant, lactating or seeking to become pregnant.