Study – Resveratrol in high doses support blood flow in the brain

By Isagenix Nutritional Sciences

Resveratrol (found naturally in grapes) is not just good for the heart, but the brain.

Resveratrol, which has previously been linked to cardiovascular health benefits and maintaining youthfulness, is now showing promise in supporting brain health.

The compound, taken orally at high doses, helps improve cerebral blood flow according to a human clinical study from the United Kingdom published recently in American Journal of Clinical Nutrition.

In the randomized, double-blind, cross-over trial, UK researchers gave 22 healthy adults a placebo (sugar pill) and two doses of trans-resveratrol at 250 milligrams and at 500 milligrams. Forty five minutes after each administration,, the subjects performed cognitive tasks to activate the frontal cortex (the part of the brain that is associated with attention, planning and motivation) for 36 minutes.

Although cognitive function wasn’t affected in this study, the trans-resveratrol resulted in a dose-dependent increase in cerebral blood flow, indexed by total concentrations of hemoglobin, during each of the tasks. Both doses of trans-resveratrol also suggested enhanced oxygen extraction, (which helps boost oxygen supply in the brain.

Why all the focus on resveratrol

Research into resveratrol, a polyphenol found naturally in grape skins and other plants, has primarily been fueled by early studies suggesting red wine has a role in creating the “French Paradox.” The paradox is that those living in France had a lower risk of cardiovascular disease despite a high-fat diet and smoking.

More recently, in 2006, a study in Nature found resveratrol protected middle-aged mice against the detrimental health effects of a high-fat, high-calorie diet. Scientists have now learned that resveratrol supports increased mitochondria synthesis, increased insulin sensitivity and improved motor function in animals.

Resveratrol as a way to obtain the benefits of eating less and exercising more is also an area of research. The compound appears to mimic the same effects on biochemical pathways as calorie restriction and increased activity with benefits clearly demonstrated with extended lifespan in rodents, fruit flies and worms.

Understanding the processes influenced by resveratrol, including how it affects mitochondria and supports release of nitric oxide, can help create a greater understanding how these processes are regulated, and ultimately how better to take control of the aging process.

How much should you get daily?

Most people obtain only a few milligrams of resveratrol in their diets daily, mainly from red wine, grapes, chocolate and peanuts. The average content of resveratrol in a typical red wine bottle is about 4 milligrams per liter and in white wine less than 1 milligram per liter.

Short-term safety studies suggest that resveratrol is well tolerated in amounts as high as 5 grams with no marked toxicity or serious adverse events.

This study’s effects were found at doses of 250 milligrams and 500 milligrams, and suggest even greater effects in the brain at doses as high as 1,000 or 5,000 milligrams daily.

Previous studies have shown that trans-resveratrol at levels of around 125 milligrams to 250 milligrams has demonstrated cardio-protective action as well as potential protection against inflammation in the body.

Because the typical North American diet does not contribute nearly enough to obtain these levels (although drinking more red wine and eating more chocolate may appeal to some) supplementation is ultimately necessary to take advantage of resveratrol’s full range of benefits.

Study reference: Kennedy DO, Wightman EL, Reay JL et al. 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;91:1590-7.