Black or green, hot or iced, tea is gaining in popularity. Many cities and shopping malls feature specialty tea shops, and bottled teas vie for space on store shelves. The Tea Association of the U.S.A. says the tea market has quadrupled over the past two decades.
Tea’s purported health benefits—many of which are linked to the heart and blood vessels—may be fueling this trend. Just how might tea help your heart, and how strong is the evidence?
“Tea is a good source of compounds known as catechins and epicatechins, which are thought to be responsible for tea’s beneficial health effects,” says Dr. Howard Sesso, associate professor of medicine at Harvard Medical School and associate epidemiologist at Brigham and Women’s Hospital. These compounds belong to a group of plant chemicals called flavonoids. Research suggests that flavonoids help quell inflammation, and that in turn may reduce plaque buildup inside arteries. Green tea has slightly higher amounts of these chemicals than black tea. Both black and green teas also contain modest amounts of caffeine, ranging from about 20 to 45 milligrams per 8-ounce cup. That’s roughly half the amount of caffeine in the same amount of coffee.