Resveratrol is known to have antioxidant properties and promote vasodilation (opening of blood vessels) thereby improving circulation.
The study referred to here was designed to evaluate blood flow to the brain since that is an important aspect of brain function (Kennedy DO, et al. 2010).
The study participants were healthy adults who either received a placebo or 2 different doses of resveratrol on separate days. After an absorption period the participants performed a selection of cognitive tasks that activated the frontal cortex of the brain.
Total concentration of hemoglobin and also oxygenated and deoxygenated hemoglobin were assessed. It was documented that resveratrol increased the cerebral blood flow during task performance in a dose dependent manner.
The researchers also found an increase in deoxyhemoglobin after the use of resveratrol suggesting enhanced oxygen extraction that was sustained throughout task performance.
This means that resveratrol improved the utilization of oxygen in the brain when the participants focused on a specific task.
Resveratrol when taken orally has a low bioavailability. By using methylated resveratrol the permeability has shown to increase approximately 5-8 folds translating into increased bioavailability (Wen X, Walle T. 2006, Walle T. 2007).
Kennedy DO, Wightman EL, Reay JL, Lietz G, Okello EJ, Wilde A, Haskell CF. Effects of resveratrol on cerebral blood flow variables and cognitive performance in humans: a double-blind, placebo-controlled, crossover investigation. Am J Clin Nutr. 2010 Mar 31.
Walle T. Methylation of dietary flavones greatly improves their hepatic metabolic stability and intestinal absorption. Mol Pharm. 2007 Nov-Dec;4(6):826-32. Epub 2007 Oct 25.
Wen X, Walle T. Methylated flavonoids have greatly improved intestinal absorption and metabolic stability. Drug Metab Dispos. 2006 Oct;34(10):1786-92. Epub 2006 Jul 25.