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Add tea to that old 'apple a day' adage.

A number of reports have suggested that, taken in moderation, alcohol -- especially wine -- may be good for the heart. What's a teetotaler to do? Drink tea and snack on apples, the results of a new Dutch study seem to indicate.

A growing body of research suggests that atherosclerosis probably traces to oxidation of low-density lipoprotein (LDL) cholesterol, the so-called bad cholesterol. This insight has prompted a search for dietary agents that might prevent LDLs from undergoing this chemical modification. The most celebrated candidates to turn up in that search: vitamin E, vitamin C, and beta-carotene (SN: 8/1/92, p.76).

The Dutch team focused on flavonoids. Trace quantities of these antioxidants -- many of them pigments -- occur naturally in plants and in drinks derived from them.

In 1985, as part of a continuing study of elderly men, the researchers conducted medical exams of 805 residents of Zutphen, the Neverlands. At the same time, they collected detailed dietary information for each participant and began chemically analyzing flavonoid concentrations in fruits, vegetables, and popular drinks. Five years later, the researchers brought the surviving participants -- now 70 to 89 years old -- back for follow-up exams and dietary surveys. Hospital or physician records confirmed the causes of death for the 185 participants who had died.

"Our study was quite small, so its [statistical] power is not large," acknowledgesd Michael G.L. Hertog of the National Institute of Public Health and Environmental Protection in Bilthoven. However, his team reports in the Oct. 23 LANCET, diets rich in flavonoids appear to cut a man's risk of dying from coronary heart disease.

For instance, 693 men entered the study with no history of heart attack. Within this group, those who consumed the most flavonoids exhibited less than one-third the risk of developing a fatal heart attack as men who consumed the least -- and that was after accounting for each man's age, diet (including consumption of other antioxidants and fats), and such other risk-modifying factors as smoking and blood pressure. The data also indicate that high flavonoid consumption reduced the incidence of nonfatal heart attacks and the first of dying from other causes.

"Vegetables and fruit were thought to be the major dietary sources of flavonoids," Hertog notes. "But in this population, the main source is tea." On average, the Zutphen men derived 61 percent of their flavonoids from the brewed beverage. Apples and onions, at 13 and 10 percent, respectively, proved the next biggest sources.

This study "reinforces the recommendation that we should eat more fruits and vegetables," says food chemist Edwin N. Frankel to the University of California, Davis. It also dovetails with test-tube findings by his group that flavonoids extracted from red wine can protect the LDLs in human blood from oxidation.

Although the Dutch study's risk analyses "are sound, I don't think anybody ought to change their habits based on them," says Arthur L. Klatsky, chief of cardiology at Kaiser-Permanente Medical Center in Oakland, Calif. "I suspect that it [the lower mortality attributed to tea] is not a statistical fluke." However, he notes that a similarly strong benefit from tea did not show up in a far larger study that he led recently.

The Zutphen data on suggest new areas for study, says Frankel. Chief among them should be analyses of flavonoid concentrations in U.S. foods, he suggests. Currently, "we lack good data on how much we consume," he notes. Equally essential, argues Ishwarlal Jialal of the University of Texas Southwestern Medical Center in Dallas, are studies on how the body handles flavonoids. They can't protect LDLs unless they reach them in the blood

--and that hasn't been shown yet, he says.
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Title Annotation:antioxidants in tea may reduce risk of death from coronary heart disease
Author:Raloff, Janet
Publication:Science News
Date:Oct 30, 1993
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