Is resveratrol responsible for the heart-health benefits found in wine? It is too early to know for sure, but scientists have found that resveratrol effectively neutralizes free radicals and other oxidants and inhibits low-density lipoprotein oxidation in the test tube. It is a well-accepted theory that oxidative stress caused by free radicals plays a crucial role in the development of atherosclerosis. In addition, resveratrol appears to possess a range of other properties, including inhibition of platelet aggregation, antiarrhythmic and vasorelaxation actions, and inhibition of apoptotic cell death that protects from myocardial ischemic reperfusion injury, atherosclerosis and ventricular arrhythmias. More research needs to occur to fully understand the relationship between resveratrol and heart health. Resveratrol may offer protection against cancer. As a possible anticancer agent, it has been shown to inhibit or retard growth of various cancer cells in culture and implanted tumors in vivo. It also inhibits experimental tumorigenesis in a wide range of animal models. The National Cancer Institute, Bethesda, MD, reports that resveratrol exhibits activities in three major steps of carcinogenesis: anti-initiation activity, anti-promotion activity and anti-progression activity. A clinical trial exploring its effects on colon cancer patients is currently underway.
Another interesting area of research involves longevity. Dietary supplementation with resveratrol may produce effects similar to calorie restriction on metabolism and longevity in mice. In mice made obese with a high-fat diet, resveratrol provided an average of 15% longer lifespan compared with those that did not receive the supplement. Resveratrol also promoted an extension in the lifespan of yeast, worms, fruit flies and a vertebrate fish. Resveratrol’s effects on longevity in higher animals needs to be investigated to gain more knowledge in this area.
The “wine pill”
Resveratrol supplements, in doses of 10 to 50 mg, have grown popular among consumers. Most U.S. resveratrol supplements come from extracts of the root of Polygonum cuspidatum. Grape and wine extracts containing resveratrol and other polyphenols are also attracting attention. Seale notes the value of grape skin and seeds that were once discarded as compost in the vineyard. “These grape extracts would be ideal to fortify a juice beverage with an antioxidant boost,” he says. “It could also be used in combination with other juices, such as blueberry, that can be tart.” Resveratrol and grape supplements have particular appeal among teetotalers; they can enjoy the benefits of red wine sans alcohol. Trans-resveratrol is an antioxidant, so will by nature oxidize with the presence of air. “In general, the matrix where trans-resveratrol is added will, to some extent, protect it from oxidation,” says Sami Sassi, product manager, Fluxome. Whether the production or process will affect oxidation, “much depends on the application itself... Granulation and microencapsulation together with premixes with other antioxidants can be applied, if required by the customer.” Scientists are just scratching the surface in this field of research, but the future looks rosy for resveratrol.
Sharon Palmer is a registered dietitian with 16 years of experience in health-care and foodservice management. She writes on food and nutrition for newspapers, magazines, websites and books. Palmer makes her home in Southern California and can be reached at
info@sharonpalmer.com.