Health Benefits of Green Tea
by Jake Mayer – www.tea-dojo.com
Scientific studies continue to show that green tea is good for you.
Tea began its illustrious history as a Chinese medicinal drink, and only gradually did it become the popular beverage that it is today. In traditional Chinese medicine, tea is considered good for you to clear the eyes and head, resolve excess phlegm, promote urination, relieve toxins, aid the digestion, and quench thirst. As with so many foods and medicines, the traditional Chinese medicinal thoughts are being proven scientifically in modern times. Today, there is ample evidence to recommend tea as a daily tonic in the interest of preventing or treating a wide range of maladies, including: cancer, hypertension (high blood pressure), high cholesterol, premature aging, food poisoning, dental decay and bad breath, and even arthritis.
Tea is rich in catechin polyphenols, particularly epigallocatechin gallate (EGCG). EGCG is a powerful anti-oxidant: besides inhibiting the growth of cancer cells, it kills cancer cells without harming healthy tissue. It has also been effective in lowering LDL cholesterol levels, and inhibiting the abnormal formation of blood clots. The latter takes on added importance when you consider that thrombosis (the formation of abnormal blood clots) is the leading cause of heart attacks and stroke.
Green tea may help dieters. In November, 1999, the American Journal of Clinical Nutrition published the results of a study at the University of Geneva in Switzerland. 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.
A Japanese report found that men who drank ten cups of green tea per day stayed cancer-free for three years longer than men who drank less than three cups a day (there are approximately 240 – 320 mg of polyphenols in three cups of green tea). Meanwhile, a study by Cleveland’s Western Reserve University concluded that drinking four or more cups of green tea per day could help prevent rheumatoid arthritis, or reduce symptoms in individuals already suffering from the disease.
Scientists at the Saitama Cancer Research Institute discovered that there were fewer recurrances of breast cancer, and the disease spread less quickly, in women with a history of drinking five cups or more of green tea daily.
Scientists also discovered that EGCG from green tea can help to prevent metastasis, or the movement and spreading of cancer cells from one organ or tissue to the other by bloodstream or lymph. Cancer cells secrete special enzymes in order to enter and colonize tissues. Research shows that EGCG stops the secretion of these special enzymes.
A case study that was done in China, reports that those women who drank green tea regularly had a 50% lower risk of developing esophageal cancer. Men showed less risk as well, but not as significant as women.
Researchers from Sweden reported that green tea blocked the development of new blood vessels in the lungs. By blocking the development of new blood vessels in the lungs, tumors are less likely to grow and metastasize. Scientists believe that EGCG plays a significant rule in blocking the development of tumors. Similar results were achieved in breast cancer, colon cancer and melanoma studies. It is believed that drinking green tea for an extended period of time will help to prevent and might cure cancer naturally.
The antioxidants found in tea–called catechins–may selectively inhibit the growth of cancer. In laboratory studies using animals, catechins scavenged oxidants before cell damage occurred, reduced the number and size of tumors, and inhibited the growth of cancer cells.
National Cancer Institute researchers are investigating the therapeutic and preventive use of tea catechins against a variety of cancers.
One Chinese study involving over 18,000 men found tea drinkers were about half as likely to develop stomach or esophageal cancer as men who drank little tea, even after adjusting for smoking and other health and diet factors.
In the laboratory, studies have shown tea catechins act as powerful inhibitors of cancer growth in several ways: They scavenge oxidants before cell injuries occur, reduce the incidence and size of chemically induced tumors, and inhibit the growth of tumor cells. In studies of liver, skin and stomach cancer, chemically induced tumors were shown to decrease in size in mice that were fed green and black tea.
Green tea catechins can help to prevent tooth decay by killing the bacteria (Streptococcus mutans) that cause dental plaque. Green tea also contains fluoride. One cup of brewed green tea contains around 0.3-0.5 mg of fluoride. This is an optimal level of fluoride according to dentists. As we all know, fluoride builds in our teeth’s enamel, making it more resistant against acidic environment, of our mouth. Green tea also eliminates other bacteria that responsible for bad breath. According to researchers, green tea polyphenols can inhibit, by 30%, the growth of bacteria that causes unpleasant breath.
A study at the Beijing Dental Hospital found consuming 3 grams of tea a day, or about 2 cups, along with the application of a tea extract reduced the size and proliferation of leukoplakia, a precancerous oral plaque.
Recent research suggests that green tea can lower cholesterol (LDL, the “bad one”) increase HDL cholesterol ( the “good one”) and lower triglyceride levels. Several tests have been done. And Green tea extract showed positive results reducing cholesterol.
At the the end of a 5 week experiment, one group with the regular diet showed blood pressure increases. For the catechin fed group, the blood pressure stayed normal. After this initial testing the scientists switched the diets for the two groups. This switch led to a reversal of the blood pressure trends. The study concluded that drinking moderate amounts of green tea each day can help to prevent high blood pressure.
The catechins in green tea have addiitonally been shown to help prevent excess cholesterol in the blood, killing the bacteria that causes food poisoning, lower blood sugar, as well as helping to control high blood pressure by supressing the production of angiotensn II. Catechin is also a strong anti-oxidant, which aids in aging related concerns.
Green and white tea leaves are less processed than oolong or black teas, which prevents oxidation and retains the highest levels of beneficial compounds. But all teas may be beneficial to your health, so find the ones you like, and drink them daily! …