If red wine and dark chocolate prevent cancer or heart disease, it is not, as was suspected, because of the antioxidant resveratrol.
Italians who consume lots of an antioxidant found in red wine, dark chocolate, and berries don’t outlive those who ingest smaller amounts and are just as likely to develop cardiovascular disease or cancer, new research shows.
“The story of resveratrol turns out to be another case where you get a lot of hype about health benefits that doesn’t stand the test of time,” says Richard D. Semba, professor of ophthalmology at the Johns Hopkins University School of Medicine. “The thinking was that certain foods are good for you because they contain resveratrol. We didn’t find that at all.”
Earlier studies did show that red wine, dark chocolate and berries do reduce inflammation in some people and appears to protect the heart, but not, apparently, because of resveratrol.
“It’s just that the benefits, if they are there, must come from other polyphenols or substances found in those foodstuffs,” says Semba, leader of the study published in JAMA Internal Medicine. “These are complex foods, and all we really know from our study is that the benefits are probably not due to resveratrol.”
Semba is part of an internatinoal team of researchers that for 15 years has studied aging in people who live in the Chianti region of Italy. For the current study, the researchers analyzed 24 hours of urine samples from 783 people over the age of 65 for metabolites of resveratrol.
After accounting for such factors as age and gender, the people with the highest concentration of resveratrol metabolites were no less likely to have died of any cause than those with no resveratrol found in their urine. The concentration of resveratrol was not associated with inflammatory markers, cardiovascular disease, or cancer rates.
Resveratrol is also found in relatively large amounts in grapes, peanuts, and certain Asiatic plant roots. Excitement over its health benefits followed studies documenting anti-inflammatory effects in lower organisms and increased lifespan in mice fed a high-calorie diet rich in the compound.
The so-called “French paradox,” in which a low incidence of coronary heart disease occurs in the presence of a high dietary intake of cholesterol and saturated fat in France, has been attributed to the regular consumption of resveratrol and other polyphenols found in red wine.
The study participants make up a random group of people living in Tuscany where supplement use is uncommon and consumption of red wine—a specialty of the region—is the norm. The study participants were not on any prescribed diet. None took resveratrol supplements, though few studies thus far have found benefits associated with them.
The NIA, the National Heart, Lung and Blood Institute, the Italian Ministry of Health, and the Spanish government supported the research. Additional researchers from Johns Hopkins, the National Institute on Aging, the New England Research Institutes, the University of Barcelona and the Catalan Institute of Oncology in Spain, and Azienda Sanitaria and the Instituto Nazionale di Ripose e Cura per Anziani V.E.II.-Instituto di Recovero e Cura a Carattere Scientifico in Italy contributed to the study.