Wednesday, September 3, 2008

Research Papers Provide Further Evidence that Tea is Steeped in Health

In a supplement to the August issue of the Journal of Nutrition, researchers from around the world published 11 scientific papers about the unique health benefits of drinking green, black and oolong tea. Although tea has been known to have medicinal properties since 2737 BC, when Chinese emperor Shen-Nung, known as the “Divine Healer,” declared tea important for the body and mind, modern-day medicine is now documenting just how tea plays role in human health and disease prevention.

The current research papers address the important and wide ranging areas of health in which tea is thought to play a role, from heart disease and certain cancers, to type II diabetes. In addition, research on the emerging role of tea for improving cognitive function and mood, preventing or reversing neurological decline and aiding in weight loss and maintenance were included.

Below, a review of the major papers and their key findings:

Boost Brain Health
Exciting new research found that a unique compound in tea, L-theanine, may act on the alpha brain waves that help us feel calm and more centered and able to focus. Using electrophysiological measures that monitor brain activity, researchers tracked brain activity after subjects received the amount of theanine equal to five to six cups of tea. The results found that activity in areas of the brain responsible for attention was enhanced and attention improved. The brain activity increased just 20 minutes after consuming theanine, and lasted about three to four hours, which may be why many people tend to drink a cup of tea every three-to-four hours.

Observational studies show that tea drinking has an inverse association with age-related dementia, Alzheimer's and Parkinson's diseases, but researchers are investigating the ways in which green tea polyphenols provide neuroregenerative properties. Israeli researchers found that when purified EGCG equal to about two to four cups of green tea per day was provided to animals with induced Parkinson’s, it appeared to prevent brain cells from dying and even to improved markers associated with neurological decline.

Defense Against Diabetes
Could a cup of tea help keep type II diabetes at bay? U.S. Department of Agriculture researchers found that tea has the ability to influence glucose metabolism and potentially reduce risk for diabetes through several mechanisms. The researchers write that in vitro animal studies have documented that compounds in tea influences glucose metabolism and enhances insulin activity. In addition, they cite human clinical trials that have found that tea consumption improved blood glucose control. However, they also caution that more studies are required to better understand the role that tea may have in the fight against type II diabetes.

Tea Drinkers Get Flavonoid Boost
Michigan State University (MSU) researchers analyzed government food pattern and consumption data to report on the differences in dietary flavonoid intake between tea drinkers and non-tea drinkers, citing that sources of flavonoid intake in free-living U.S. adults have not yet been reported. According to the MSU researchers, tea was the most prominent source of flavonoids from food and beverages in the U.S. diet. They found that the diets of tea drinkers had over 20 times the flavonoids (697.9 vs. 32.6) of non-tea drinkers. Flavonoid intake is inversely associated with the incidence of many chronic diseases, and may be one of the chief reasons why tea offers such a healthy punch.

While some of the studies published are considered preliminary, there are no known health risks associated with drinking tea--and only the prospect of myriad health benefits. Please visit for access to the studies.

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