International Tea and Health Symposium

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Tea�s Healthy Attitude Proclaimed at 2007 International Tea and Health Symposium

By Bruce Richardson

One of the many marvels of tea is the seeming contradiction that this ancient beverage calms the mind as it stimulates our ability to concentrate. That phenomenon was only one of several topics covered at the recent 2007 International Tea and Health Symposium, held at the Department of Agriculture in Washington, DC.

Tea�s mysterious ability to both calm and stimulate has been recorded in Chinese lore and Buddhist practice for centuries. During a symposium press briefing, this enigmatic virtue caused a perplexed radio reporter to sputter �but how can one beverage cause the brain to react in both ways?� The frustrated reporter was responding to a finding presented by John Foxe, Ph.D., Professor of Neuroscience, Biology and Psychology at City College of the City University of New York. It took the modern invention of the MRI machine to map tea�s effect on the complex workings of the human brain. Dr. Foxe and his team used electrophysiological measures to monitor brain activity after individuals drank solutions containing 250 mg of the amino acid theanine. Theanine is present almost exclusively in the tea plant. After drinking tea, the amino acid theanine is absorbed by the small intestine and cross the blood-brain barrier where it affects the brain's neurotransmitters, and increases alpha brain-wave activity. This alpha brain rhythm is known to induce a calmer, yet more alert, state of mind. "Our results showed that after having theanine, individuals showed significantimprovement in tests for attention and activity in cortical regions responsible for attention functions was enhanced," said Dr. Foxe.

EGCG � Tea�s Powerful Component

The big news that came out of the last symposium, held in 2003, was green tea�s possible effect on cancer cells. The buzz word since then has been EGCG, teas principle catechin and a strong antioxidant. Researchers worldwide are now looking at EGCG�s effect on overall human health. Over one thousand professional papers dealing with tea and health were published in 2006. One of the promising new areas of study is tea�s, and consequently EGCG�s, effect on Parkinson�s and Alzheimer�s diseases. Dr. Silvia Mandel, of the Eve Topf Center for Neurodegenerative Diseases in Haifa, Israel, has been studying the effects of EGCG on the neurological health of animal models. She and her team found that green tea EGCG appeared to prevent brain cells from dying. EGCG treatment also showed improvements in reducing compounds that lead to lesions in the brains of animals with Alzheimer�s disease. According to Dr. Mandel, "not only may the EGCG help prevent brain cells from dying, it appears that the polyphenol may even rescue the neurons once they have been damaged, to help them repair.� It�s worth noting that the Michael J. Fox Foundation is funding a current study on tea�s effects on Parkinson�s disease.

Flavonoids

Tea, red wine, cocoa and many fruits and vegetables are rich in flavonoids, a type of antioxidant. Adding flavonoids to the diet shows positive effects on chronic diseases, including cardiovascular disease and certain cancers.

Using the latest national food consumption databases and the USDA flavonoid database, Michigan State University researchers were able to differentiate tea drinkers from non-tea drinkers and analyze their diets for flavonoid intake.

"We found that the total flavonoid intake of tea consumers was more than 20 times higher than flavonoid consumption of non-tea drinkers," explained lead researcher Won Song, Ph.D., R.D. Professor of Human Nutrition at Michigan State University.

Tea drinkers averaged nearly 700 mg flavonoids while non-tea drinkers averaged about 33 mg per day. A cup of tea contains approximately 125 mg flavonoids, which is more than most non-tea drinkers consume in an entire day.

A diet rich in flavonoids could improve blood vessel function. New research presented by Claudio Ferri, M.D., Professor of Internal Medicine at the University of L'Aquila in Italy provided additional insights into how tea flavonoids provide support for cardiovascular health. "Our studies have found that tea flavonoids brought about a decrease in arterial stiffness, suggesting that tea consumption may have favorable effects on cardiovascular disease," he reported. His studies also showed tea�s positive effects on reducing blood cholesterol levels and providing dilation of blood vessels to help manage blood pressure.

Tea and Weight Management

With over two-thirds of the U.S. adult population overweight or obese, scientists are looking for medically sound ways to help consumers manage their weight. Eva Kovacs, Ph.D., Clinical Research Manager at Unilever North America, reviewed the existing scientific literature on green tea, weight loss and metabolism. Dr. Kovacs looked at several research studies conducted in recent years that suggest that green teas may aid in weight management by reducing body fat and in particular visceral fat. "A few studies have found modest benefits on metabolism from green tea extract, but more research is needed before recommending drinking green tea as a 'fat burner,'" said Dr. Kovacs.

Consumers worldwide are being offered a host of ready-to-drink teas that tout tea�s ability to reduce weight and speed metabolism. Dr. Kovacs warned consumers that green tea products are no magic bullet for weight loss and should only be included as part of an overall diet and exercise strategy to

achieve a healthy body weight.

Diabetes

The Department of Agriculture is spending significant time and money studying America�s soaring incidence of diabetes. Their preliminary research has led them to look to tea as a possible solution because individuals with diabetes have increased levels of oxidative stress. Since tea is high in anti-oxidants, tea or tea compounds may have an independent effect on insulin signaling and glucose metabolism. Dr. David Baer, USDA Research Physiologist, reported that preliminary studies point to tea consumption and a reduced risk of type 2 diabetes.

The Tea Industry�s Role

One of the leading spokesmen for tea�s role in a healthy lifestyle has been Dr. Jeffery Blumberg, Professor of Nutrition Science and Policy at Tufts University. Dr. Blumberg was one of the moderators for the 2007 Symposium. He likes to point out that it's not surprising that the health benefits of drinking tea has led to a robust body of literature that is very promising. Plants are known to have potent bioactive compounds, which is why diets rich in plant-based foods are known to support the body's fight against many chronic conditions associated with aging and disease. Research continues to show that tea contains bioactive compounds that have biological roles within human cells.

"The data presented at this year's symposium extends the apparent benefits of tea beyond reducing the risk for cardiovascular disease and cancer to new facets of health,� said Dr. Blumberg. He went on to warn tea professionals that it is premature to label their products with health claims that may, or may not, be proven in further clinical trials. �You should wait until all the evidence is in before marketing tea as anything more than a healthy beverage.�

This article first appeared in the November 2007 edition of Fresh Cup magazine.

Tea�s Healthy Attitude Proclaimed at 2007 International Tea and Health Symposium

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