A glass of fine red wine can elevate a good meal to a fantastic one or help unclench the mind after a difficult day. Yet some scientists believe those salubrious effects of le vin rouge pale next to what one of its ingredients may someday do. Perched upon that wineglass stem, masked in crimson, is a molecule that may hold enormous potential for human health: resveratrol.

The substance that has become synonymous with red wine’s health benefits was actually first isolated from the roots of white hellebore, a flowering plant, in 1940. But resveratrol got scant attention until 1992, when researchers found an abundance of it in red wine and postulated that resveratrol might explain what’s known as the “French paradox.” The paradox is this: France is saturated, so to speak, with foods rich in unhealthy fats—cheeses, cream sauces, foie gras, and the ubiquitous croque-monsieur, a gooey grilled ham-and-cheese sandwich. Yet the French have a surprisingly low rate of heart attack and stroke (although some researchers argue the numbers have been underestimated). And what do the French wash all that fatty deliciousness down with? That’s right: red wine. The thinking goes that perhaps it’s the resveratrol in the wine that keeps the French healthy in spite of a well-larded diet.

Even if the French paradox is eventually disproven, resveratrol research is showing promise. Some data suggest that resveratrol may keep blood from clotting, much like aspirin. There is also evidence that it relaxes blood vessels, exerts an antioxidant effect, and keeps cholesterol and tri­glycerides from forming the arterial lesions that can cause heart attacks and strokes. What’s more, resveratrol has the potential to help more than just the heart, it seems. One of the most exciting areas of research is cancer prevention and treatment. In studies of mice, a topical application of resveratrol reduced skin tumors by 98 percent, and a hefty oral dose increased nerve cancer survival rates by 70 percent.

But what works in mice doesn’t necessarily work in people. “In humans, we aren’t very far along,” says Joseph Baur, PhD, an instructor in the Department of Physiology at the University of Pennsylvania, although resveratrol’s effect on people is being actively studied. Many of the animal studies have required extremely high doses of resveratrol to produce any effect, and the molecule eventually becomes toxic. Resveratrol metabolism may be to blame: Some scientists think the molecule breaks down too rapidly in the body to be of any benefit. Researchers are trying to tweak resveratrol so that it lingers in the body and can be used in lower doses in human studies.

People with type 2 diabetes may be among the first to benefit from this research, if the positive results of early clinical trials withstand further scrutiny. The trials tested a slowly metabolized version of resveratrol called SRT501, created by a Boston company named Sirtris that was bought last year by pharmaceutical giant GlaxoSmithKline. Last year, Sirtris announced that SRT501, taken once or twice daily, was safe and lowered blood glucose levels in people with type 2 diabetes. A study is just finishing up of SRT501’s effects on people with type 2 who take metformin but whose blood glucose remains uncontrolled. Sirtris is also developing agents that act like resveratrol but are chemically distinct and more potent. The small Sirtris studies so far have been designed to assess the safety of the drugs but did show some benefits. Yet for a drug to win Food and Drug Administration approval, it needs to show both safety and efficacy in longer trials that include a large number of people. It could be years before these Sirtris products can be prescribed—if they ever make it that far.