Editor's Note: In early 2012, the University of Connecticut announced that a three-year investigation of Professor Dipak Das found extensive evidence he had falsified data in certain studies. It is unclear yet which of Das' studies are compromised, but his findings on wine and polyphenols are now under question.
A leading researcher’s review of more than a hundred studies of resveratrol, the red-wine compound that has spurred millions of dollars of investment by pharmaceutical and nutritional companies, raises more questions than it answers. According to the study, there is substantial evidence that resveratrol can lower the risk of deadly diseases, such as diabetes, heart failure and some types of cancer. But it seems to offer little help at extending lifespan.
Early research found evidence that resveratrol might slow aging on a cellular level. Numerous nutritional supplement companies still tout this when marketing various resveratrol products.
But Dipak Das, a researcher at the University of Connecticut’s Cardiovascular Research Center, reviewed more than 100 studies on resveratrol and said there is no scientific basis for that conclusion. The meta-analysis, titled "Erratum to: Resveratrol and red wine, healthy heart and longevity," refers to the emerging doubts of resveratrol as an anti-aging compound. It is slated for publication in Heart Failure Reviews.
In early studies, resveratrol was linked to extending the lifespans of fruit flies and tropical killifish. But once the studies moved on to mammals, scientists found that while disease rates still declined with the consumption of resveratrol, the animals didn’t live longer.
The conclusions are puzzling, Das said, because it appears that resveratrol should be able to increase the length of life—researchers found the chemical manipulates genes and increases longevity on the cellular level. "Resveratrol is so powerful it can activate stem-cell survival," Das said. "So why is it not extending lifespan, by improving the survivability of genes?"
Das said his research shows the limitation of modern science to deeply delve into the issue. For one, real longevity research on humans should involve humans, he said, and should last for decades. "If you want answers to the longevity of mammals, it will take years and years of dedication," he said. "Right now, we can only offer a snapshot and that isn't powerful enough."
There’s another practical reason, one that involves funding and career paths. A top resveratrol researcher from Harvard, David Sinclair, found a few years ago that resveratrol may mimic the effect of caloric restriction in humans. This is the only known way to extend life, Das writes in his study. Not to be confused with starvation, which increases metabolism and therefore hastens death, caloric restriction involves controlled limited calorie intake. (It appears to activate a genetic response that extends life when food is scarce, allowing animals to survive until supplies improve and they can reproduce.)
But most research dollars—both public and private—don’t go to studies focused on abstract concepts like anti-aging. The money goes to fight specific illnesses. Armed with evidence that resveratrol lowered the risk of Type-2 diabetes, Sinclair opened Sirtris Pharmaceuticals in an effort to develop drugs based on resveratrol that could treat various diseases.
GlaxoSmithKline soon purchased the company and began trials with several synthetic variants of the polyphenol. Glaxo would later halt one study focused on a resveratrol variant that led to complications. Competitors Pfizer and Amgens also experienced setbacks and could not verify Sinclair's earlier resveratrol results in subsequent lab tests, the study states.
On the anti-aging front, no one else stepped in to fill Sinclair's shoes. "For some reason we all stopped looking into [the anti-aging aspect] after Sinclair's study came out three years ago," Das said.
What Das’ work illustrates is that resveratrol still holds many mysteries. It appears that science is still at the starting line.