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As small nutrients go, few have commanded the same media attention as resveratrol, a compound found in red wine, berries, peanuts and some medicinal plants. In fact numerous lab studies have suggested resveratrol may fight aging, cancer and inflammation.

But as scientists have moved from the lab to human clinical trials, the claims haven't panned out, according to a broad review of research into the antioxidant.

That doesn't mean resveratrol isn't an important nutrient, but its importance hasn't been proven in human trials, say the authors of "Resveratrol and Health: A Comprehensive Review of Human Clinical Trials," which is being published in the journal Molecular Nutrition and Food Research.

That hasn't kept resveratrol from becoming the darling of supplement manufacturers and anti-aging crusaders alike, who often claim resveratrol is the reason the French population has low incidence of cardiovascular disease, despite a diet high in saturated fats and wine. In fact, one study found that a resveratrol supplement is taken by more than 60 percent of people who routinely take multiple dietary supplements.

Early lab and animal studies have shown promise. Some mice studies have pointed to anti-carcinogenic properties, while other data suggests resveratrol may delay or attenuate many age-related changes and prevents early mortality in obese animals.

Yet, there have been nearly 4,000 published studies of the antioxidant--almost all done in a petri dish or animal models. Only a few have been done in humans and those have failed to draw the same conclusions, the authors say.

The study suggests that drug companies may be unwilling to fund research into resveratrol because it is a natural substance and any medications created from it may be hard to profit from.

And human studies that have looked at the nutrient have run into problems. For example, many of the beneficial effects observed in lab studies may not work in humans because we process resveratrol too quickly. Any positive effects observed in red wine consumption may also be due to other chemicals, the researches said.

The authors said future human research should look at how different dosages of resveratrol affects outcomes and measurable amounts of the chemical in the body; study resveratrol versus existing alternatives; and determine if the nutrient will compliment other therapies and what the long-term effects of resveratrol supplements might be.

The study's authors are from the University of Florida, Marywood University and the University of Pennsylvania School of Medicine.