WASHINGTON -- Red wine surrendered a clue to its health benefits in a study suggesting Madiran, a traditional French wine, may be brimming with one of the more valuable ingredients for protecting the heart.
Scientists found the most potent form of polyphenols, which help reduce the risk of artery damage, in Madiran, and lesser amounts in other wines from southwestern France and Italy's Sardinian province of Nuoro.
People in those regions also tend to live longer than those in surrounding areas, according to the study, in today's issue of the journal Nature.
Consumers have shifted to smoother wines over the past 15 years, while studies of health benefits focused on groups of people who drink more robust traditional red wines as part of a healthy diet, lead investigator Roger Corder said in a telephone interview from Cornwall, England.
"This may be highlighting that not all wines confer the same benefit," said Corder, a professor of experimental therapeutics at Queen Mary, University of London. "The Madiran wines are by far the best in terms of their style and their structure and just the classical way that they're made."
The Tannat black grape used to produce Madiran contained the most potent of the ingredients, called procyanidins, according to research conducted primarily at William Harvey Research Institute at Queen Mary in London. Old-fashioned winemaking also extracts the most procyanidins from grapes, the scientists said.
"Grape seeds are the main source of these polyphenols called procyanidins," Corder said. "We also know that dark chocolate is another rich source of it."
Nuoro Province on the island of Sardinia in the Mediterranean has about 24 people 100 years old or older per 100,000 people, compared with an average of about seven to 10 per 100,000 in most populations, Corder said.
Madiran is produced in the department of Gers, an area of France that has twice as many 90-year-olds as other areas, he said.
Corder has received funding for research and to attend symposia from Catena Wines, made by Bodegas Catena Zapata SA in Mendoza, Argentina, and Canandaigua Wine Co., owned by Constellation Brands Inc. in Fairport, N.Y.
He said he expects to see clinical trials with dark chocolate and grape-seed extract and possibly a pill containing the most beneficial ingredients in at least a decade. The red wines researched are those best consumed with food, Corder said.
He himself enjoys good wine.
"I can't deny that that was the stimulus to start me on the research about 10 years ago," Corder said.