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WHITE PLAINS, NEW YORK — NOVEMBER 13, 2007 — reported today that its tests of supplements containing resveratrol — a compound promoted as "life-extending" — revealed two products providing only 27% and 58% of their listed amounts of resveratrol. A third product, which boasted several hundred milligrams of a "red wine grape complex," contained only two milligrams of resveratrol. Several other products contained their listed amounts of resveratrol, although daily doses ranged from just 1 milligram to as much as 1,000 milligrams. None of the products were contaminated with lead or cadmium, which can occur in plant-based supplements.

Resveratrol products have proliferated following reports late last year of life-extending and athletic endurance-enhancing activity in animals. Laboratory research has also shown antioxidant, anti-inflammatory, anticancer, and other effects. Human studies of its effectiveness have not been reported, but at least one researcher in the field, Dr. David Sinclair at Harvard Medical School, is noted as taking resveratrol personally at a dose of approximately 350 mg per day.

Along with widely ranging dosage suggestions on products, found similar variation in the cost of resveratrol. To obtain 100 mg of resveratrol from any product, the cost ranged from as little as $0.20 to as much as $45.57 — more than a 22,000% difference. Using the lowest cost product that passed's testing, the daily cost for a dose of 300 to 400 mg would be $0.60 to $0.80 per day. To get that dose from any of the products with single digit milligram amounts of resveratrol would be impractical — requiring hundreds of pills per day and costing as much as $159. For some products, the price difference may reflect the cost of additional ingredients.

"I am not surprised that some resveratrol supplements failed to meet their ingredient claims," said Tod Cooperman, MD, President of which has tested more than two thousand supplements since 1999. "When an ingredient quickly becomes popular as a supplement, we often see products rush to market that range widely in quality, dose, and price. There is still much to learn about resveratrol. At least now those who choose to use it can find out which products contain what they claim and which do not."

The report is available at It includes findings for nine products selected by as well as four that passed's Voluntary Certification Program. Brands included are French Parad'ox (Arkopharma), Purevinol (Pure Prescriptions), Resvert (Young Again), Resvera-Gold (Douglas Laboratories), Revatrol (Renaissance Health), Transmax (Biotivia), Vinotrol (NeXtten), and Zyflamend (New Chapter), as well as products from Country Life, Jarrow Formulas, Life Extension, Longevinex, and Swanson. The report also provides information regarding the dosage and possible side-effects. is a leading provider of consumer information and independent evaluations of products that affect health and nutrition. Reviews of popular types of vitamins, supplements, and generic drugs are available at Soon to be released are new Product Reviews of omega-3 and -6 fatty acids, potassium, and turmeric. Subscription to is available online. The company is privately held and based in Westchester, New York. It has no ownership from, or interest in, companies that manufacture, distribute, or sell consumer products.

For further information, contact Tod Cooperman, MD, at

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