The Health Benefits of Drinking Green Tea Continue to Grow

The Green Tea Benefits Are Growing With More Research

Proponents of green tea note that its medicinal benefits have been described for over 1000 years. The Kissa Yojoki, or Book of Tea, written by Zen priest Eisai in 1191, describes how drinking green tea can have a positive effect on the five vital organs, especially the heart. The book discusses tea's medicinal qualities, which include easing the effects of alcohol, acting as a stimulant, curing blotchiness, quenching thirst, eliminating indigestion, curing beriberi disease, preventing fatigue, and improving urinary and brain function. In more recent times, many studies have investigated a link between the consumption of green tea and a lower incidence of a range of cancers in populations, with mixed results. Green tea enthusiasts believe it to be useful for:

• Cognition
• Stopping certain neurodegenerative diseases such as Alzheimer's
• Preventing/treating cancer
• Treating arthritis
• Treating multiple sclerosis
• Preventing the degradation of cell membranes by neutralizing the spread of free radicals (which occurs during the process of oxidation).
• Increases fat oxidation (helps the body use fat as an energy source) and raises metabolism.
• Lowering LDL cholesterol (in high doses in lab tests)
• Preventing lowered T-Cells due to HIV - In lab tests, EGCG, found in green tea, was found to prevent HIV from attacking T-Cells. However, it is not known if this has any effect on humans yet.

The U.S. Food and Drug Administration (FDA) has rejected claims of health benefits for green tea.

• "There is no credible scientific evidence that drinking green tea reduces the risk of heart disease."
• "FDA concludes there is no credible evidence to support qualified health claims for green tea or green tea extract and a reduction of a number of risk factors associated with CVD" (cardiovascular disease)."
• The FDA has said that green tea likely does not reduce breast, prostate, or any other type of cancer risk.

Although a 2006 study published in the September 13 issue of the Journal of the American Medical Association shows that adults who consumed three or more cups of green tea per day had a lower risk of death due to cardiovascular disease. The study, conducted by the Tohoku University School of Public Policy in Japan, followed 40,530 Japanese adults, ages 40-79, with no history of stroke, coronary heart disease, or cancer at baseline beginning in 1994. The study followed all participants for up to 11 years for death from all causes and for up to 7 years for death from a specific cause. Participants who consumed 5 or more cups of tea per day had a 16 percent lower risk of all-cause mortality and a 26 percent lower risk of cardiovascular disease than participants who consumed less than one cup of tea per day. The study also states, "If green tea does protect humans against CVD or cancer, it is expected that consumption of this beverage would substantially contribute to the prolonging of life expectancy, given that CVD and cancer are the two leading causes of death worldwide."

A 2006 study published in The American Journal of Clinical Nutrition (Vol. 83, pp 355-361) showed that elderly Japanese people who drank more than 2 cups of green tea a day had a 50 percent lower chance of having cognitive impairment than those who drank less or who consumed other tested beverages. The high amount of catechins found in green tea is thought to be the reason.

In May 2006, researchers at Yale University School of Medicine weighed in on the issue with a review article that looked at more than 100 studies on the health benefits of green tea. They pointed to what they called an "Asian paradox," which refers to lower rates of heart disease and cancer in Asia despite high rates of cigarette smoking. They theorized that the 1.2 liters of green tea that is consumed by many Asians each day provides high levels of polyphenols and other antioxidants. These compounds may work in several ways to improve cardiovascular health, including preventing blood platelets from sticking together and improving cholesterol levels, said the researchers, whose study appeared in the May issue of the Journal of the American College of Surgeons. Specifically, green tea may prevent the oxidation of LDL cholesterol (the "bad" type), which, in turn, can reduce the buildup of plaque in arteries, the researchers wrote.

Green tea has also been claimed to reduce stress and produce alpha waves. This is thought to be due to high antioxidant levels and the presence of l-theanine, which is a glutamate analog present in green tea that can cross the blood-brain barrier and reduce glutamate excitotoxicity during stress and ischemia.

A German study found that an extract of green tea and hot water (filtered), applied externally to the skin for 10 minutes, three times a day could help people with skin damaged from radiation therapy (after 16-22 days). A study in Japan indicated that people ages 40-79 who drank five or more cups a day were 16 percent less likely to die within the 11-year study period, compared to people who drank only one cup a day.

Green tea is also a potent fat burner. People who took green tea extract three times a day saw their metabolic rate increase by about 4 percent, according to a study published in the December 1999 American Journal of Clinical Nutrition.

Japanese researchers claim if you drink five cups of green tea a day, you'll burn 70 to 80 extra calories. Dr. Nicholas Perricone , an anti-aging specialist, appeared on the Oprah Winfrey show and told Oprah's viewers they can lose 6 lbs. in 10 weeks drinking green tea instead of coffee.

Source: Wikipedia