Green Tea and Your Health – a short summary
No other food or beverage is reported to have as many health benefits as green tea and the evidence keeps growing.
The Chinese have known about the medicinal benefits of green tea since ancient times and historical details that surround it’s earliest origins are sketchy and are constantly being debated. One thing that is for certain is that the Chinese have used it to treat everything from rheumatism, headaches, anxiety and depression. In her book Green Tea: The Natural Secret for a Healthier Life, Nadine Taylor states that green tea has been used as a medicine in China for at least 4,000 years.
Today there is an avalanche of contemporary scientific research in both Asia and the West that is providing hard evidence for the purported health benefits associated with drinking green tea. The mounting research and testimonials have been very promising. Take one example from a study done in 1994 by the Journal of the National Cancer Institute. They published the results of an epidemiological study indicating that drinking green tea reduced the risk of cancer of the esophagus in Chinese men and women by nearly sixty percent! Researchers at the University of Purdue have recently concluded that unique compounds (catechins and flavonoids) in green tea inhibits the growth of cancer cells. (for more information click here) Current research has also indicated that drinking green tea lowers total cholesterol levels as well as improving the ratio of good (HDL) cholesterol to bad (LDL) cholesterol.
Just a few medical conditions in which drinking green tea is reputed to be helpful are cancer, rheumatoid arthritis, high cholesterol levels, cardiovascular disease, infection and impaired immune function.
What Is It That Makes Green Tea So Unique?
The secret of green tea lies in the fact that it is rich in catechin polyphenols (or flavonoids), particularly epigallocatechin gallate (EGCG). EGCG is a powerful anti-oxidant. EGCG inhibits the growth of cancer cells and also kills cancer cells without harming surrounding healthy tissue. Green tea has also been shown to be effective in lowering LDL cholesterol levels in the body and also at inhibiting the abnormal formation of blood clots. This feature of catechins takes on added importance when one takes into consideration the fact that thrombosis (the formation of abnormal blood clots) is the leading cause of heart attacks and strokes.
Links are being made between the effects of drinking green tea and the “French Paradox.” For years scientists have been perplexed by the fact that despite having a diet consisting of foods that are high in fat the French have a lower incidence of heart disease than Americans do. The answer has been found to lie in red wine. Red wine contains resveratrol, a polyphenol that limits the negative effects of smoking and a diet high in fat. In a 1997 study, researchers from the University of Kansas determined that EGCG is twice as powerful as resveratrol, which may explain why the rate of heart disease among Japanese men is quite low, even though approximately seventy-five percent are smokers. Quite a testimonial to the benefits of green tea if it were the only factor considered! However, when taking into account the fact that European and Asian males simply walk more than Americans the findings can only be considered to be promising at best.
Why is it then that other Chinese teas don’t have the same health-giving properties? Green, oolong, and black teas all come from the leaves of the Camellia sinensis plant. What sets green tea apart is the manner in which it is processed. Green tea leaves are steamed, which prevents the EGCG compound from being oxidized. By contrast, black and oolong tea leaves are made from fermented leaves, which results in the EGCG being converted into other compounds that are not nearly as effective in preventing and fighting various diseases.
Are There Any Benefits for Weight Loss?
New evidence is emerging that green tea can even help dieters. A study released by the American Journal of Clinical Nutrition in 1999 published the results of a study performed at the University of Geneva in Switzerland. Swiss researchers found that men who were given a combination of caffeine and green tea extract burned more calories than those given only caffeine or a placebo.
Green tea can even help prevent tooth decay. Just as its bacteria-destroying abilities can help prevent food poisoning, it can also kill the bacteria that causes dental plaque. Meanwhile, skin preparations containing green tea – from deodorants to creams – are starting to appear on the market including those that purportedly reverse the loss of hair.
Is There A Potential for Harmful Effects?
To date, the only negative side effect reported from drinking green tea is insomnia due to the fact that it contains caffeine. It is a fact, however, that green tea contains less caffeine than coffee. There are approximately thirty to sixty milligrams of caffeine in six to eight ounces of tea compared to over one hundred milligrams in eight ounces of coffee.