A new study casts more doubt upon the health benefits of resveratrol, the red wine antioxidant that has garnered so much interest from researchers and the public over the last decade. The compound, found in red wine and chocolate, two indulgences that many of us have consumed with noble regularity, has been accumulating less robust evidence in the last few years. Some animal studies have suggested that in high doses the compound may have benefits like reducing inflammation and extending the lifespan. Others, including the current study, published in JAMA Internal Medicine, haven’t found many effects at all in people. But that doesn’t mean you should give up on it completely.
The researchers looked at urine samples of 783 people living in the Chianti region of Italy and measured levels of resveratrol metabolites. They tracked which participants died over the course of nine years, and of what causes. The unexpected finding was that there were no links between resveratrol levels and the risk of death. There were also no correlations between resveratrol and inflammation, heart disease or cancer.
“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,” said study author Richard D. Semba of 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.”
But part of the issue may come down to dosing. “The levels of Resveratrol in the diet are negligible compared to the levels shown to work in mice and humans,” Harvard University researcher David Sinclair told the LA Times. Sinclair is one of the leading resveratrol researchers in the U.S. Many people have pointed out it would be virtually impossible to get high enough levels in the diet as are used in research studies.
But some people try. According to the new study, resveratrol supplements have become a $30 million a year industry in the U.S. Unfortunately, “there is limited and conflicting human clinical data demonstrating any metabolic benefits of resveratrol, and there are no data concerning its safety in high doses or for long-term supplementation in older people.”
Still, there’s something responsible for what’s known as the “French Paradox,” referring to the fact that French people often consume diets high in saturated fat and cholesterol, but have unusually low levels of heart disease. Researchers had suggested that resveratrol might be responsible for the effect, since it’s found in foods like grapes, berries, peanuts, chocolate, and, of course, red wine. But a number of studies have cast doubt as to whether that’s the case at all.
“It’s just that the benefits, if they are there, must come from other polyphenols or substances found in those foodstuffs,” says Semba. “These are complex foods, and all we really know from our study is that the benefits are probably not due to resveratrol.”
The study was small, however, and more research will be needed to understand the compound further.
So don’t quit the resveratrol yet, at least if you’re getting it and other antioxidants from the diet. It may still have some health benefits, particularly in the way of reducing inflammation in the body. While you may not want to be part of the $30 million resveratrol supplement industry until there’s some more consistent evidence on its behalf, a little dark chocolate and red wine every now and then may still do you good.