Retail supermarket sales of tea passed $2.15 billion in 2010

If you enjoy wrapping your hands around a warm cup of tea, you may want to make it a habit. And grab a second and third cup as well because the evidence continues to mount that the brew is good for you.

Heart health is the most notable benefit, says Jeffrey Blumberg, director of the Antioxidant Research Laboratory at Tufts University: "People who drink more tea do appear to have less risk of heart disease, and for those who have developed some cardiac event like a heart attack, those who are tea drinkers seem to have a lower incidence of a second event."

Green tea vs. black tea: It's really no contest

The protective effects of tea, the second-most-consumed beverage in the world after water, has been the focus of thousands of scientific studies, says Joseph Simrany, president of the Tea Association of the USA, a trade group.

Much of that research has focused on green tea but "the data from green and black are really overlapping," says Blumberg. Not too surprising, he says, since popular varieties of tea — green, black, oolong and white — are from the same evergreen shrub, the Camellia sinensis, and the difference is from levels of maturity when picked and oxidation when processing.

So-called herbal teas or tisanes, are not teas, but infusions of boiled water with leaves, roots, bark and/or flowers.

Researchers suspect that natural components in tea, particularly a class of polyphenol antioxidants known as flavonoids, are responsible for tea's health benefits. Blumberg says the nutrients are "very similar to those that you find in fruits and vegetables, in tree nuts, in soy." By drinking tea "you're adding more plant food to your diet," he says.

Tea's increasingly high health profile has propelled its popularity. Retail supermarket sales passed $2.15 billion in 2010; for the first time ever, more tea was imported into the USA than the United Kingdom.

Tips for maximum health benefits

Ready-to-drink tea (canned/bottled and refrigerated) is nearly half of the $7.8 billion U.S. tea market. Ready-to-drink and instant teas, like most home-made iced tea, are diluted, so you're not getting as strong a dose of flavonoids as you would from a cup of freshly brewed hot tea, says Blumberg. For optimum flavonoids, he says, drink tea soon after it's brewed.

When you add sugar or buy it sweetened, you turn a zero-calorie beverage that's great for hydrating the body and has half the caffeine of coffee into a drink "loaded with sugar and calories, sometimes as much as soda," says registered dietitian Andrea Giancoli, an American Dietetic Association spokesperson. The effect of adding milk to tea is unclear, Blumberg says

How much should you drink? "Three cups throughout the day is prudent from a physiological point of view," says Lenore Arab, a nutritional epidemiologist and tea researcher at the University of California-Los Angeles. "Many healthy populations drink as many as six cups per day."

Tea is for two (or even more):

Not everyone who sips tea is focused on potential health benefits. Tea enthusiasts like Katrina Ávila Munichiello enjoy a cup primarily for its many other fine qualities.

Not only is there a world of tastes and flavors to explore, but preparing and drinking tea provides "a quiet time to think and contemplate," says Munichiello, author of A Tea Reader: Living Life One Cup at a Time. In it, she shows the impact of tea on the lives of a cross section of tea lovers.

Tea is a wonderful catalyst for conversation