The Secret Power of Green Tea

by Carole Jackson, Bottom Line Health

Yes, we live in a coffee society. Hellooo Starbucks! But even at that shrine to the roasted bean, you can order lots of different kinds of teas, too. Next time you find yourself there or in another beverage shop, you might want to order yourself a piping hot cup of green tea, which has bountiful health benefits. I was reminded of this once again when I attended a lecture on the topic by Mark Blumenthal, founder and executive director of the nonprofit American Botanical Council.


While green, black and oolong teas all come from the same plant, Camellia sinensis, and theoretically offer similar health benefits, the truth is that the green tea we drink usually is far better for us because it has undergone the least amount of processing. Some types of tea must be fermented — the leaves wilt, and then they are bruised and rolled, which results in the leaves being fully oxidized. But with green tea, the wilting is halted by using dry or steam heat, so the leaves are only dried. This allows them to remain exceptionally rich in natural polyphenol antioxidants known as catechins, Blumenthal explained. The most powerful of these is epigallocatechin-3-gallate (EGCG), which acts as a kind of superhero antioxidant in your body to wipe out free radicals that damage genetic material in cells and cause disease.

Blumenthal noted that there actually has been an explosion of research on green tea over the past decade. Blumenthal and I reviewed some of the stand-out findings…

  • Lower heart risk. Numerous studies demonstrate that green tea can lower your risk for cardiovascular disease.
  • Explore green tea’s anticancer potential. A variety of population-based research suggests that green tea protects against cancer — in other words, cancer rates tend to be lower in Asian countries, where people regularly consume the beverage. And in one recent study of more than 500 people in Taiwan, investigators found that people (including both smokers and nonsmokers) who did not drink green tea experienced more than five times the risk for lung cancer compared with participants who drank at least one cup a day.
  • Slim down with a cup of tea. In a clinical trial of more than 100 overweight adults ages 21 to 65, half had about two cups (about 16 ounces) of a catechin-containing beverage that included green tea extract each day while the other half drank a placebo beverage that did not contain green tea. All engaged in 180 minutes weekly of moderate exercise and were asked to eat what they normally eat throughout the study. After 12 weeks, members of the catechin group had shed more abdominal fat and showed greater improvement in their triglyceride (blood fat) levels than the control group. Results were published in the February 2009 Journal of Nutrition.


Following an extensive review of the data on green tea, Blumenthal told me that he believes that most health benefits begin to accrue with about five cups per day. My first reaction was, wow, that’s a lot of tea — but he explained that this refers to five of the five-ounce cups common in Asia, which translates to about three of our Western-style mugs.

Generally speaking, said Blumenthal, the teas with the most nutrients are almost always sold in bulk as “leaves” as opposed to in tea bags. Brewing tea in bags is more convenient for most people, but if you want more bang for your buck, buy the leaves. You can buy either caffeinated or decaffeinated green tea. Some experts think that decaffeinated tea may have fewer nutrients, but Blumenthal doesn’t know of any data that supports this.

To preserve the tea’s antioxidants, store the leaves or bags in a cool, relatively dark area. How you take your tea — such as with milk, sugar or honey — doesn’t appear to affect the health benefits of tea, said Blumenthal. Just be sure to steep the tea for two to five minutes to get the most polyphenols — and if you’re using a bag, dunk it up and down.


Mark Blumenthal, founder and executive director, American Botanical Council (, an independent, nonprofit organization dedicated to disseminating accurate, reliable and responsible information on herbs and medicinal plants. Blumenthal is the editor/publisher of HerbalGram, an international, peer-reviewed quarterly journal.