美国英语听力80篇2 Lesson35
Chocolate
New studies say that eating chocolate may be good for your heart.
Research shows that eating chocolate may reduce the chance of developing heart disease
by helping blood vessels remain clear and open.
Chocolate is produced from beans that contain large amounts of natural substances called flavonoids.
Flavonoids have been shown to protect the heart and the blood vessels from damage.
Recent studies have linked foods that contain flavonoid with a reduced chance of developing heart disease.
These foods include tea, red wine, apples, peanuts and chocolate.
Research has shown that forty grams of milk chocolate contain about 400 milligrams of flavonoid.
That is about the same amount in a glass of red wine.
The same amount of dark chocolate contains more than 800 milligrams of flavonoid.
That is about the same amount as a cup of black tea.
A study by researchers at the University of Scranton in Pennsylvania
found that the flavonoid in chocolate are more powerful
than some vitamins in limiting the damage from fats in the blood.
A German study recently showed that the flavonoid in chocolate also could stop damage to blood vessel walls.
And a University of California study showed that flavonoid from chocolate produce nitric acid in the blood.
Nitric acid helps protect the walls of blood vessels.
A study by Cesar Fraga of the University of Buenos Aires in Argentina confirmed healthy activity in the blood
after eating dark chocolate,
Carl Keen of the University of California at Davis also carried out studies about flavonoid.
The studies showed that foods high in flavonoid might help stop thickening of the blood
that can lead to heart attacks or strokes.
Mister Keen gave water, cocoa or nonalcoholic red wine to groups of ten men and women.
Researchers tested their blood a few hours later.
Both the wine and cocoa delayed the time it took for the blood to become solid.
Only the cocoa protected platelets in the blood from becoming too sticky and breaking.
Some of the studies about chocolate were paid for by the Mars company which makes many kinds of chocolate candy.
All the researchers agreed that many more studies are needed to confirm their findings
