Botanical: Camellia sinensis
Family: Theaceae (tea)
Green Tea is an ancient and potent tonic that is believed to boost the immune system. It is said to possess potent antibacterial, antiviral and anticarcinogenic properties, and the Chinese have used this natural antioxidant for centuries to revitalize and prolong life. Green Tea is also rich in fluoride and may help to reduce tooth decay. Heart- healthy, eye-healthy, brain-healthy Green Tea may also be helpful as a tool in weight management regimens.
"If thou art cold, tea will warm thee.
If thou art hot, tea will cool thee.
If thou art sad, tea will cheer thee.
If thou art cross, tea will calm thee."
Nineteenth Century British Prime Minister
The information presented herein by Herbal Extracts Plus is intended for educational purposes only. These statements have not been evaluated by the FDA and are not intended to diagnose, cure, treat or prevent disease. Individual results may vary, and before using any supplements, it is always advisable to consult with your own health care provider.
It is said that a Chinese emperor who lived five thousand years ago was boiling water when a sudden gust of wind swept some leaves from the branches of a nearby small tree and dropped them into his kettle. The leaves turned the hot water a deep, rich color and released an enticing aroma, which the Emperor cautiously tasted - and the great cultural and social tradition of Tea drinking was born in China. Tea has been used as a medicinal beverage to promote health of mind and body since that time and was even recorded as a medicinal aid in China as early as 2737 B.C. Green, Oolong and Black teas are the true teas derived from the same tea plant; they are simply processed differently. Although these are the principal categories of Tea, the Chinese classify tea (cha) with as many as 330 kinds. The Tea plant is an evergreen shrub or tree that is native to the rainy forests of Southeast Asia and may grow to thirty feet, but is usually maintained at a height of five feet by regular pruning. It has been cultivated in Burma, India, Japan, Turkey, Malawi, Argentina, Sri Lanka, Pakistan, Africa and China, where it has been consumed as a beverage and medicinal tonic for five thousand years. The production process that produces Green Tea does not allow oxidation to take place, and because it is not "fermented," the active constituents remain unaltered and stronger. Green Tea is high in polyphenols that are said to possess potent antioxidant and anticarcinogenic properties. The catechin in the polyphenols called epigallocatechin gallate (EGCG) is said to be over two-hundred-times more powerful than the known antioxidant, vitamin E, in neutralizing free radicals. Most of the Tea produced in the world is Black Tea, with only twenty percent processed as Green Tea, which is primarily consumed in China, Japan and a few countries in North Africa and the Middle East. Several of the constituents included in Green Tea are astragalin, volatile oils, beta-carotene, beta-sitosterol, caffeine, cinnamic acid, eugenol, isoquercitrin, lutein, lycopene, procyanidins, quercetin, rutin, salicylic acid, tannic acid, amino acids/methylxanthines (theophylline, theobromine and theanine), calcium, iron, magnesium, manganese, phosphorus, potassium, zinc, B-vitamins, tacopherol and vitamin C. The primary constituents of interest are the polyphenols, which include flavanols, flavandiols, flavonoids and phenolic acids. Most of the polyphenols in Green Tea are flavonols, commonly known as catechins. Some major Green Tea catechins are (-)-epigallocatechin-3-gallate (EGCG), (-)-epigallocatechin (EGC), (-)-epicatechin-3-gallate (ECG), (-)-epicatechin (EC), (+)-gallocatechin, and (+)-catechin (5). The polyphenols are believed to be responsible for most of Green Tea’s role in promoting good health.
According to a study published in the Journal of the American Medical Association, Green Tea is associated with decreased early death, from all causes, including cardiovascular disease. Interestingly, these results were not linked with other types of tea, like oolong or black tea, indicating the antioxidants specific to Green Tea could be the cause. For more details about this, read the article
Green Tea Gulpers May Have a Reduced Risk of Early Death; Antioxidants May Be the Reason .
Green Tea is said to be a powerful stimulant that increases energy and may be useful in weight loss programs. According to 2010 research from Berlin, Germany's University of Medicine, a daily dose of Green Tea extract,
epigallocatechin gallate (EGC), was associated with a 33 percent increase in fat oxidation, while a daily dose of Green Tea's caffeine was linked to a 34.5 percent increase, but when male subjects were given a combination of Green Tea's EGCG and caffeine, fat oxidation increased by almost fifty percent! Three mechanisms have been proposed: EGCG could increase energy metabolism and fatty acid oxidation; inhibit fat cell development (apidogenesis); and/or reduce lipid absorption and increase fat excretion.
Green Tea also has a stimulating effect on the brain that may increase alertness, perhaps because of its caffeine content. In a 2006 study published in The American Journal of Clinical Nutrition, the research showed that elderly Japanese people who drank more than two cups of Green Tea a day had a fifty percent lower chance of having cognitive impairment than those who consumed less or who consumed other tested beverages. The high amount of catechins found in Green Tea is thought to be the reason. In 2012, research from Switzerland's University Hospital, Basel, suggests that Green Tea catechin extracts
(i.e., polyphenols epigallocatechin gallate [EGCG], epigallocatechin, epicatechin gallate and epicatechin), may enhance brain function and boost working memory. Further 2012 research from China's Third Military Hospital discovered that the Green Tea compound epigallocatechin-3-gallate (EGCG) provides benefits to memory and special learning by boosting production of important progenitor neural cells and enhance learning and memory by improving object recognition and spatial memory.
Green Tea is reported to lower total cholesterol and blood pressure. It is said to stabilize blood lipids and may therefore be of value in an overall cardiac care regimen. In recent lab studies, Green Tea inhibited an increase in serum cholesterol, even when on an artery-damaging diet. Green Tea has been shown to improve the cholesterol profile by decreasing LDL “bad” cholesterol and increasing HDL “good” cholesterol, and may also promote cardiovascular health by making platelets in the blood less sticky. Green Tea has also been shown to protect against damage to LDL (“bad”) cholesterol caused by oxygen, and consumption of Green Tea is said to enhance antioxidant activity in the blood. Oxidative damage to LDL can promote arteriosclerosis. Researchers, whose study appeared in the May, 2006, issue of the Journal of the American College of Surgeons, indicated that the high levels of polyphenols and antioxidants in Green Tea may work in several ways to improve cardiovascular health, including preventing blood platelets from sticking together and improving cholesterol levels. They wrote that the compounds that are found specifically in Green Tea may prevent the oxidation of LDL cholesterol (the bad kind), which, in turn, can reduce the buildup of plaque in arteries. In May, 2006, researchers at Yale University School of Medicine weighed in on the issue with a review article that looked at more than one hundred 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 Green Tea consumed by many Asians each day provides high levels of polyphenols and other antioxidants.
Green Tea is a highly regarded tonic that is used to boost the immune system. The polyphenols in Green Tea act as powerful antioxidants that have been shown to lower the risk of several types of malignancy by blocking the formation of damaging free-radical compounds, suppressing the activation of carcinogens and detoxifying disease-causing agents. The forms of cancer that appear to be best affected by Green Tea are those of the gastrointestinal tract (stomach, small intestine, pancreas, colon), lung and estrogen-related (breast, ovarian). The polyphenol called catechin from Green Tea has also been said to effectively inhibit metastasis (uncontrolled spread) of melanoma cells on the skin.
In regard to cancers, studies have suggested that the combination of Green Tea and one of its main components, the powerful EGCG (epigallocatechin-3-gallate), can be beneficial by providing protection against certain types of cancers, including breast cancer. In 2012, scientists from
New York City’s Columbia University Medical Center discovered that another Green Tea
extract called Polyphenon E appears to inhibit vascular endothelial growth factor and hepatocyte (liver cell) growth factor, both of which promote tumor cell growth, migration and invasion. In the study,
the women assigned to the extract had an average 10-fold increase in Green Tea metabolites (involved in normal growth) and a significant reduction in hepatocyte growth factor levels. In 2013, scientists at the U.S. National Cancer Institute found that
daily consumption of Green Tea may reduce the risk of developing breast cancer by modifying estrogen metabolism.
With respect to prostate cancer research, a study conducted in 2012 at
the University of California, Los Angeles, found that
Green Tea consumption may reduce the risk for prostate cancer and lower serum prostate-specific antigen (PSA) by opposing processes such as inflammation (nuclear factor kappa B)
, which are associated with prostate cancer growth. In addition, Italian research revealed that men with a precursor to prostate cancer called prostatic intraepithelial neoplasia who consumed a Green Tea extract reduced their risk for progression to prostate cancer.
In a 2007 study reported in a journal of the American Association for Cancer Research, it is said that in order to get the full benefits of the catechins in Green Tea, you might need to take Green Tea supplements (capsules or pills), or else expect to spend all your waking moments brewing and sipping. The study said that it took concentrated Green Tea in supplements that were equal to eight to sixteen cups a day to boost production of enzymes that make carcinogens less toxic.
Green Tea has demonstrated antibacterial and antiviral activity and appears to have the capacity to reduce periodontitis and minimize bad breath; and its high fluoride content is thought to help reduce dental caries. The polyphenols in Green Tea have been shown to have topical antibacterial properties, even against the bacteria that cause dental plaque. Further research (2010) indicated that higher polyphenol/catechin concentrations in Green Tea extracts may improve dental health and reduce the risk of losing teeth.
Regarding the issue of plaque formation, the substance epigallocatechin-3-gallate (EGCG), extracted from Green Tea, interferes with the aggregation process of the mutant protein in Huntington's Disease.
Moreover, cytoxicity is also reduced. In an article published in the journal, Human Molecular Genetics (September, 2006), Dr. Wanker, of the Charité - Universitätsmedizin, Berlin, hopes these findings will provide future medical treatment for Huntington's Chorea and related diseases. Huntington's Disease, along with Alzheimer's and Parkinson's, belong to the family of neurodegenerative diseases caused by protein misfolding.
The theophylline content in Green Tea is said to relax and soothe the muscles supporting the bronchial tubes, thereby reducing the problems associated with bronchitis and mild cases of asthma.
Traditional Chinese Medicine (TCM) recommends Green Tea for headaches (it contains salicylic acid, the natural precursor to synthetic aspirin), body aches, indigestion and depression. In TCM, it is considered an energizing tonic that promotes detoxification, enhances the immune system and prolongs life. Modern research has confirmed many of these health benefits.
In two separate studies, Green Tea flavonoids, given by capsule, reduced fecal odor and favorably altered the gut bacteria in elderly Japanese living in nursing homes with - and without - feeding tubes. These studies indicate a potential for using Green Tea in other situations, where gut bacteria are disturbed, such as after taking antibiotics.
According to new research from China’s Hong Kong Eye Hospital and the University of Hong Kong, Green Tea catechins could help protect against glaucoma and other eye diseases by protecting the eye against oxidative stress, which cause biological disturbances, such as DNA damage and activation of proteolytic enzymes that can lead to tissue cell damage or dysfunction that eventually lead to many ophthalmic diseases, including cataract formation, damaged retinal tissue cells and glaucoma.
In 2008, studies that were reported in the National Library of Medicine
demonstrated that drinking Green Tea during benzene exposure can reduce several parameters indicative of oxidative stress. As such, as a dietary supplement, Green Tea could represent a potential therapeutic agent in reducing certain aspects of benzene-induced toxicity.
Benefits of Drinking Green Tea
- From ABC7.com, KABC-TV Los Angeles - 07/27/06
"When it comes to fighting cancer, especially breast cancer, USC Preventive Medicine experts say go for Green Tea instead of black. Dr. Anna Wu examined the dietary habits of Asian American women. She found those who drank Green Tea exclusively showed the most benefit. "They had about a forty percent reduction in risk of breast cancer and these were women who were daily tea drinkers," Wu said. Both Green and Black Tea are made from the leaves of the Camellia sinensis plant, but Black Tea is fermented much longer than Green Tea," a process that destroys certain polyphenols."
"The Art of Tea" ~ How Teas are Processed
- From our own Herbal Extracts Plus research - 08/06
Did you know that Green, Oolong, Black and White Teas are all derived from the same plant? They are simply processed differently. Read this article to find out how those processes will affect your good health and why the process that produces Green Tea does not allow oxidation, keeping all its potent antioxidant properties intact. After reading these important facts, you may just decide to purchase a different tea the next time you are at the grocery store.
Pregnant women or those who take blood thinners should not use Green Tea. People who use ginseng regularly or those taking patent medicine (especially codeine) should consult their doctors before using Green Tea. The most common adverse effect reported from consuming large amounts of Green Tea (many times the recommended daily dosage) is insomnia, anxiety and other symptoms caused by the caffeine content in the herb. Must take with a meal. In rare cases extracts from Green Tea have been reported to adversely affect the liver. Discontinue use and consult a healthcare practitioner if you have a liver disorder or develop symptoms of liver trouble, such as abdominal pain, dark urine or jaundice. Patients undergoing cancer therapy with Velcade should not take Green Tea extracts, since it may interfere with the drug's efficacy.