Red Wine is Rich in Fiber, According to Spanish Study
Moderate consumption of red wine may contribute to one's recommended daily intake of fiber
Correction: This article reported that daily consumption of 300ml (about two glasses) of red wine could contribute almost 7 percent of the recommended daily fiber intake in Spain. It should have said that consuming 300ml of red wine would increase a Spaniard's average daily intake of soluble dietary fiber by up to 6.9 percent. (In the United States, based on the Institute of Medicine's recommended daily intake of total fiber for men aged 19 to 50, the same two glasses of red wine would contribute up to 1.1 percent of total fiber.) Likewise, the two white wines averaged would increase daily intake of soluble fiber by 1 percent to 2 percent.
New research from Spain is giving a double meaning to the term "regular red-wine drinkers." According to a study in the March issue of the American Journal of Enology and Viticulture, red wine contains significant amounts of dietary fiber. White wines do not contain as much.
Drinking 300 milliliters of red wine a day could contribute up to 7 percent of the fiber needed to reach the recommended daily intake in Spain, the researchers reported. (That level of consumption amounts to about 1.1 percent of the U.S. daily value for total fiber.) Co-author Fulgencio Sauro-Calixto, of the department of metabolism and nutrition at the Instituto del Frio in Madrid, said that the findings are positive because the average Spaniard is believed to be fiber-deficient. Likewise, the average American doesn't consumer enough fiber, according to the American Gastroenterological Association.
"Average dietary fiber intake in Europe ranges from 16 to 21 grams per day. In Spain, intake is 5.20 grams per day," said Sauro-Calixto, adding that the country's recommended intake is 30 grams per day. In the United States, the recommended daily value is 25 grams, while the average intake is about 11 grams per day. "Wine and beverages are not taken into account in studies on dietary fiber, and consequently, daily intakes may be underestimated," Sauro-Calixto added.
Grape juice and grape pomace were already known to have high levels of fiber, but the Spanish scientists were unable to find any data for wine, prior to their study. It was originally assumed that wine contains no dietary fiber, they wrote.
The scientists picked five red wines and two whites from several regions in Spain for their experiment. Tempranillo was present in all the reds; the Ribera del Duero and Rioja were 100 percent Tempranillo, while the variety was included in the blends of the wines from La Mancha (along with Merlot), Jumilla (Monastrell) and Penedès (Merlot and Cabernet Sauvignon). The whites, from La Mancha and Rueda, were made of Macabeo blended with Viura and Verdejo, respectively.
The researchers vacuum-distilled the wines to remove the alcohol and make it easier to detect the polysaccharides found in fiber. They also used specific enzyme treatments to isolate any dietary fiber so that it could be measured. A third treatment, using dialysis, eliminated all other constituents of the wine aside from the fiber.
The red wine from Jumilla had the most fiber, at 1.37 grams per liter, while the wine from La Mancha had the lowest level, at 0.94 grams. By averaging the results for all the reds, the scientists concluded that 300 milliliters of wine per day--or about two 5-ounce glasses--offers almost 7 percent of one's recommended daily intake of fiber in Spain.
The level of fiber in the white wines stood at 0.19 grams per liter for the Rueda and 0.39 grams for the La Mancha. When averaged, the white wines provided between 1 percent and 2 percent of one's recommended daily intake of fiber.
The scientists speculated that winemaking practices are most likely responsible for the higher level of fiber in red wine. In particular, red-wine must spends much more time in contact with grape skins.
Sauro-Calixto said that it is still too early to apply the results of his research. He recommended that people consume 200 to 300 milliliters of red wine daily, "mainly in the prevention of cardiovascular diseases. But the biological properties and health significance of fiber, in the context of wine consumption, remain to be elucidated."
