Chocolate Can Keep Cardiovascular System in Shape
A bit of the right kind can help dilate arteries
TUESDAY, June 1, 2004 (HealthDayNews) -- For those who think the world is a bitter place, medical science offers this sweet health tidbit: Chocolate might be good for you.
Not just any chocolate, and always in moderation, said Mary Engler, a professor of physiological nursing at the University of California, San Francisco, School of Nursing. But her new study does find that biting into the right stuff can make arteries expand, increasing blood flow and thus reducing cardiovascular risk.
Milk chocolate won't do, Engler stressed, because it's, well, too milky. Look for darker chocolates, because darkness is an indicator of high levels of flavonoids, the chemicals that loosen up the arteries.
And this is one instance where good taste and good health go hand in hand, Engler said.
You can tell that a chocolate has a high flavonoid content because "the flavor is so intense and rich," she said.
The study that Engler and her colleagues are reporting in the Journal of the American College of Nutrition had 11 willing participants eat 1.6 ounces of flavonoid-rich chocolate every day for two weeks. Another 10 volunteers, sacrificing themselves for science, consumed an equal amount of low-flavonoid chocolate.
Ultrasound measurements showed that expansion of the arteries in response to greater blood flow increased by 10 percent in the flavonoid consumers, while there was a slight decrease in those who got the flavonoid-poor chocolate. Blood levels of a powerful flavonoid, epicatechin, rose more than eightfold for the high-flavonoid group and remained unchanged for the others.
The study was done in collaboration with the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University. Jeffrey Blumberg, chief of the center's Antioxidant Research Laboratory, said the work has expanded to look at other flavonoid-containing foods.
"Not only chocolate, but also tea, oat bran, almond skins and blueberries, all are good sources of flavonoids," Blumberg said. "We're trying to get a better understanding of vital chemicals, flavonoids being one of the larger groups."
Chocolate "happens to be a rich source of flavonoids," Blumberg said, but he added that "we are not trying to position chocolate as a health food."
In addition to flavonoids, chocolate also has a lot of calories and a lot of saturated fat, neither of which is good for the arteries, he said.
"But in the context of a reasonable diet, chocolate is not only a pleasurable food but might contain some health-promoting ingredients," Blumberg said.
Recommendations about chocolate can be compared with those about wine, Engler said. An occasional glass or two of wine has been shown to be associated with a reduced risk of cardiovascular disease, she said, "but people should not be overindulgent with wine. The same is true of dark chocolate in moderation as part of a well-balanced diet."
You can explore the frontier of chocolate research by consulting the Chocolate Information Center.