Interest in green tea for its purported health benefits has spurred dozens of organizations to fund studies experimenting with green
tea and its counterpart, white tea. These particular tea samples will be sent in for a study focused on caffeine (an alkaloid found naturally in plants like coffee and cocoa;
caffeine is technically called theine in tea).
According to Sanders, there are two main reasons for this set of tests. "First, to answer questions from consumers about caffeine, which is
our most frequently asked question," he said. "But also to understand what it is about tea that makes you feel so good."
Caffeine Study
Caffeine is known by medical science to play a role in wellness, reducing headaches and stimulating metabolic and chemical activities in the body.
But too much caffeine raises stress levels and can be unhealthy. In tea, how much of a factor is caffeine (theine)?
According to the lab report, Dragon Pearl's green tea is actually higher in caffeine than black tea over three steepings of whole leaves.
The experiment tested white, green, black and oolong teas steeped three times at 180 degrees Fahrenheit.
The most surprising result? All the teas tested contained more caffeine than an average cup of coffee, the possible exception being oolong tea. An average cup of coffee has roughly 100mg of caffeine, while the green tea contained about 200mg per cup, indicating that caffeine may play a big role in the feeling of wellness one gets from a cup of tea.
"All real tea comes from the camellia sinensis plant," explained Sanders. "But it's not all the same. This tea is very fresh, and extremely potent due to its
growing environment. The conditions in the mountains where this tea is farmed are ideal for the photosynthesis and glycolysis cycles the plants need to develop
compounds of flavor and phytonutrients, which is why we selected these teas." But when it comes to health, he adds, what everyone is most interested in is how tea helps fight cancer.
Antioxidant Study
Using Brunswick's high-tech ORAC Hydro Testing method at their lab in Boston revealed what was already suspected: green tea varies greatly in potency with
age and oxidation.
(Oxidation describes the loss of electrons by a molecule, atom or ion, which occurs in tea when it is exposed to air.) Lab reports indicate that whole-leaf tea
maintains its potency, while ground tea leaves become stale very quickly and lose potency.
The teabag sample that tested highest was a leading brand of leaf flakes (not finely ground) in individually-wrapped airtight bags.
Still, it tested well under 500 mgTE/g, compared with over 750 mgTE/g for Dragon Pearl's fresh whole-leaf tea.
Purity Study
A comparison of "regular" teabags one might find in a grocery store versus organic mountain-grown tea also yielded unsurprising results: the cheaper teas are
grown in areas that don't have pure soil, air or water, causing the pollutants in the environment to taint the tea with higher-than-acceptable levels of
heavy metals like lead
and other impurities.
Tests conducted at Anresco Labs also reveal traces of pesticides in most commercial teas. Some of the chemicals that show up in commercial teas include
bactericides, fungicides and insecticides. "Many teas grown in India, China, Africa and even
US use pesticides or chemical fertilizers," says Sanders. "I wouldn't drink that tea if you paid me." By definition, he adds, organic teas are grown without
chemicals and must be lab tested for purity before being certified by an agency or approved by a government.
2008 Anti-Carcinogen/Antibacterial Studies
Phytonutrients are certain organic components of plants, and these components are thought to promote human health. Natural tea contains high levels of
the plant polyphenol Epigallocatechin-gallate (EGCG), which have been shown to resist and destroy both cancer and bacteria in a number of these recent studies.
According to the American Cancer Society, scientific evidence suggests that about one-third of the 565,650 cancer deaths expected to occur in the U.S. in 2008
will be related to overweight or obesity, physical inactivity, and nutrition and thus could also be prevented. In addition, certain cancers are related to
infectious agents and could be prevented through behavioral changes, vaccines, or antibiotics. In both of these areas-fighting
infectious disease and battling cancer directly-tea has delivered some exciting blows.
In April 2008, Dr. Mervat Kassem from the Faculty of
Pharmacy at Alexandria University in Egypt announced results from a study indicating that drinking enhanced the effectiveness of antibiotics. "We tested green tea in combination with antibiotics against 28 disease causing micro-organisms belonging to two different classes," reported Dr. Kassem.
"In every single case green tea enhanced the bacteria-killing activity of the antibiotics. For example, the killing effect of
chloramphenicol was 99.99% better when taken with green tea than when taken on its own in some circumstances."
Concurring with Dr. Kassem, studies in China also reveal the ability of white tea on its own to fight bacterial infections such as Staphylococcus.
According to a report at the Vanderbilt Epidemiology Center published by the American Association for Cancer Research,
tea and its constituents have also shown anti-carcinogenic activities both in vitro and in animal studies; however, epidemiological results aren't always consistent.
The study evaluated the association between green tea consumption and colorectal cancer, and found through statistical comparisons that the reduction in risk
was most evident among those who consistently reported to drink tea regularly.
At the Experimental Biology 2008 conference, Jian-Wei Gu of the University of Mississippi Medical Center reported the effects of the green tea antioxidant on several indicators of breast cancer growth in laboratory mice. The results indicated that treatment with a green tea antioxidant solution decreased tumor size by 66% and weight by 68% compared with the control group.
This new information builds on studies from last year, which offer evidence that drinking green tea can prevent bladder infections (ScienceDaily,
May 21, 2007), fight lung cancer (WebMD, March 12, 2007), and may even be therapeutic for people with arthritis. (ScienceDaily, April 30, 2007).
How Much Is Too Much?
Given the mounting evidence that green tea is a way to fight or at least help prevent cancer, companies are scrambling to offer supplements
and cures in pill form. But is there risk of too much caffeine when using green tea or polyphenol supplements?
Not unless you really overdo it, according Dr. Davaasambuu Ganmaa of the Harvard School of Public Health in Boston, Massachusetts.
His study of over 5,000 women found no correlation between increased caffeine and breast cancer.
"Coffee and tea are remarkably safe beverages when used in moderation," said Ganmaa.
Mr. Sanders agrees. "Also, most people report that green tea has a much gentler curve than coffee, with a smoother 'take-off' and 'landing,'" compared to coffee, he says.
And any whole-leaf tea can be pre-steeped to remove up to 50% of the caffeine, according to Sanders. "In most tea, it's not the caffeine I'm worried about.
It's the impurities."
Green and white teas have the highest levels of EGCG, while oolong tea is known to help weight loss by improving metabolism and breaking down fats.
But while a tea plant grows, it absorbs impurities and heavy metals like lead and aluminum from the soil and water.
Not All Green Tea Is Created Equally
"The less expensive teas are machine-farmed in the lowlands, and do not offer the potency, purity or flavor of organic mountain teas," explains Sanders.
Higher potency due to ideal growing conditions might explain the high levels of caffeine as well as antioxidant potency. "Common belief is that tea has less caffeine than coffee," he says. "We're not sure what tea they're
testing. But it sure isn't this tea." According to the most recent lab tests, you can remove about 50% of the caffeine in tea by
pre-steeping for two minutes. (Commercial teas labeled "decaffeinated" are 97 to 98 percent caffeine free after undergoing ethyl acetate or carbon dioxide processes.)
(More about green tea)
ANRESCO Laboratories is based in San Francisco, providing independent analysis for food and nutrition industries.
Anresco produces quality analytical research resulting in data that is defendable, ethical, and accurate.
More information is available at anresco.com.
Brunswick Laboratories Brunswick Laboratories, founded in 1997, is an independent contract laboratory
providing analytical services in the chemical sciences and dedicated to improving health through science.
More information is available at brunswicklabs.com.
Dragon Pearl Tea, based in Grover Beach, California, imports fresh whole-leaf
teas from exclusive organic farm co-ops in the mountains of Fujian, China.
More information is available at dragonpearltea.com.
ADDITIONAL REFERENCES
American Cancer Society:
http://www.cancer.org
Cancer Epidemiology Biomarkers and Prevention:
http://cebp.aacrjournals.org
Chinese-American Tea Association (CATA):
http://teaassociation.org/
Port of Long Beach:
http://www.portoflosangeles.org
Science Daily:
http://www.sciencedaily.com
