By David Blyweiss, M.D.

A few years back, researchers decided that resveratrol was the secret ingredient in red wine that was responsible for the so-called “French paradox.” Not only could it protect the heart from oxidized fat, resveratrol also appeared to reduce platelet aggregation and increase blood flow. The problem was, no one knew how much resveratrol was needed to create these heart-healthy changes … until now.

New research conducted at the University of South Australia suggests that taking a daily resveratrol supplement can rapidly improve vascular function and lead to better heart health. The study, which was published online in Nutrition, Metabolism & Cardiovascular Diseases, is the first to evaluate the immediate effects of resveratrol supplementation on circulation.

Specifically, it shows that resveratrol improves flow-mediated dilation (FMD)—a marker of cardiovascular function. Impaired FMD is linked to several cardiovascular risk factors including high blood pressure and obesity, and is characterized by structural and functional changes to the lining of blood vessels. But, the researchers found that—depending on the dose—taking a resveratrol supplement triggered positive changes in the lining of the blood vessels. As a result, more blood is able to flow through the arteries and veins.

The key to resveratrol’s beneficial effects are the polyphenols it contains. These compounds—which are also found in berries, green tea, olives and walnuts—prevent platelets from sticking together, boost antioxidant status and increase the availability of nitric oxide, the chemical in the body that dilates blood vessels. How important is nitric oxide (NO)? Endothelial dysfunction can occur when the body doesn’t release enough NO. Without sufficient amounts of NO, blood vessels constrict and limit the amount of blood that travels to vital organs and the far reaches of the body like hands, feet and even the brain.

In this study, the researchers compared different doses of supplemental resveratrol—30, 90 and 270 mg.—with a placebo in 19 overweight or obese subjects. They found that the higher the dose, the higher the blood concentrations of the nutrient. In fact, taking 270 mg. of supplemental resveratrol increased blood plasma concentrations from 4.1 percent to 7.7 percent. That, in turn, improved FMD significantly by boosting NO availability.

Of course, resveratrol’s impact on NO and FMD aren’t its only claim to fame. Other research shows that resveratrol may be linked to a reduced risk of inflammation and blood clotting, both of which can lead to heart disease. It can also benefit your cholesterol ratio. A recent review in the European Journal of Clinical Nutrition concluded that resveratrol reduced LDL (bad) and total cholesterol, and increased HDL (good) cholesterol. While HDL carries artery-clogging cholesterol to the liver to be processed and eliminated from the body, high LDL cholesterol can lead to the kind of plaque buildup that subsequently contributes to clogged arteries.

Resveratrol has important antioxidant properties as well. Antioxidants, found naturally in fruits and vegetables with deep rich colors, help prevent chronic disease and even some types of cancer by reducing the cellular damage that occurs during natural bodily processes like breathing and energy metabolism. Without antioxidants to counter this damage, the DNA in cells can mutate and have impaired function.

Finally, resveratrol suppresses inflammation by cutting off the chain reaction that produces inflammatory chemicals in the body. This is significant because inflammation is associated with the progression of atherosclerosis, the fatty plaque buildup that leads to stiff, narrow arteries, and ultimately, heart attacks and strokes.

If you’re at risk for heart disease, I recommend adding 200 to 600 mg. of resveratrol to your daily supplement regime. But be aware that all resveratol supplements are not created equal. To get the most from your resveratrol, look for a standardized supplement that provides 10 mg. of trans-resveratrol, the most biologically active form of the nutrient.

References:

Rius C. Trans- but not cis-resveratrol impairs angiotensin-II-mediated vascular inflammation through inhibition of NF-kappaB activation and peroxisome proliferator-activated receptor-gamma upregulation. Journal of Immunology. 2010;185:3718-3727.

Wong RHX. Acute resveratrol supplementation improves flow-mediated dilatation in overweight/obese individuals with mildly elevated blood pressure. Nutrition, Metabolism & Cardiovascular Diseases. Published online ahead of print, doi: 10.1016/j.numecd.2010.03.003.

Yap S. Effects of resveratrol and flavonols on cardiovascular function: Physiological mechanisms.Biofactors. 2010 Aug 27. [Epub ahead of print]