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Title: Green Tea Health Effects
Source:
Wikipedia
URL Source: http://en.wikipedia.org/wiki/Green_tea
Published: Sep 28, 2009
Author: Staff
Post Date: 2009-09-28 19:36:32 by Horse
Keywords: None
Views: 66
Comments: 3
Green tea contains polyphenols which are thought to improve health, particularly catechins, the most abundant of which is epigallocatechin gallate. In vitro and animal studies as well as preliminary observational and clinical studies of humans suggest that green tea can reduce the risk of cardiovascular disease and cancer as well as beneficially impact bone density, cognitive function, dental cavities, and kidney stones. However, the human studies are sometimes mixed and inconsistent.[6] Green tea also contains carotenoids, tocopherols, ascorbic acid (vitamin C), minerals such as chromium, manganese, selenium or zinc, and certain phytochemical compounds. It is a more potent antioxidant than black tea,[6] although black tea has substances which green tea does not such as theaflavin. Green tea consumption is epidemiologically associated with reduced heart disease, and animal studies have found that it can reduce cholesterol. However, several small, brief human trials found that tea consumption did not reduce cholesterol in humans. In 2003 a randomized clinical trial found that a green tea extract with added theaflavin from black tea reduced cholesterol.[7] In a study performed at Birmingham (UK) University, it was shown that average fat oxidation rates were 17% higher after ingestion of green tea Extract than after ingestion of a placebo.[8] Similarly the contribution of fat oxidation to total energy expenditure was also significantly higher by a similar percentage following ingestion of green tea extract. This implies that ingestion of green tea extract can not only increase fat oxidation during moderately intensive exercise but also improve insulin sensitivity and glucose tolerance in healthy young men. A recent study looked at the effects of short term green tea consumption on a group of students between the ages of 19- 37. Participants were asked not to alter their diet and to drink 4 cups of green tea per day for 14 days. The results showed that short term consumption of commercial green tea reduces systolic and diastolic BP, fasting total cholesterol, %body fat and body weight. These results suggest a role for green tea in decreasing established potential cardiovascular risk factors. This study also suggests that reductions may be more pronounced in the overweight population where a significant proportion are obese and have a high risk of cardiovascular disease.[9] In a study performed at the Technion, it was shown that the main antioxidant polyphenol of green tea extract, EGCG, when fed to mice induced with Parkinson's and Alzheimer's disease, helped to protect brain cells from dying, as well as 'rescuing' already damaged neurons in the brain, a phenomenon called neurorescue or neurorestoration. The findings of the study, led by Dr. Silvia Mandell, were presented at the Fourth International Scientific Symposium on Tea and Human Health in Washington D.C., in 2007. Resulting tests underway in China, under the auspices of the Michael J. Fox Foundation, are being held on early Parkinson's patients.[10] In a recent case-control study of the eating habits of 2,018 women, consumption of mushrooms and green tea was linked to a 90% lower occurrence of breast cancer.[11] [edit] History Tea consumption had its origin in China more than 4000 years ago.[12] Green tea has been used as both a beverage and a method of traditional medicine in most of Asia, including China, Japan, Vietnam, Korea, India and Thailand, to help everything from controlling bleeding and helping heal wounds to regulating body temperature, blood sugar and promoting digestion. The Kissa Yojoki (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. Part One also explains the shapes of tea plants, tea flowers, and tea leaves, and covers how to grow tea plants and process tea leaves. In Part Two, the book discusses the specific dosage and method required for individual physical ailments. [edit] Unproven claims Green tea has been credited with providing a wide variety of health benefits, many of which have not been validated by scientific evidence. These claims and any for which academic citations are currently missing are listed here: Stopping certain neurodegenerative diseases such as Alzheimer's and Parkinson's. The prevention and treatment of cancer.[13][14] Treating multiple sclerosis.[15] Preventing the degradation of cell membranes by neutralizing the spread of free radicals which occur during oxidation process.[16][dubious – discuss] Reducing the negative effects of LDL cholesterol (bad cholesterol) by lowering levels of triglycerides and increasing the production of HDL cholesterol (good cholesterol). Joy Bauer, a New York City nutritionist, says [the catechins in green tea] increase levels of the metabolism speeding brain chemical norepinephrine (noradrenaline). Japanese researchers claim that drinking five cups of green tea a day can burn 70 to 80 extra calories. Dr. Nicholas Perricone, a self-proclaimed anti-aging specialist, appeared on The Oprah Winfrey Show and told Oprah's viewers they can lose 10 lbs (4.5 kg) in 6 weeks drinking green tea instead of coffee. Some green tea lovers commonly restrict their intake because of the stimulants it contains — equivalent to about a third the amount of caffeine as is found in coffee[4][dubious – discuss]. Too much caffeine can cause nausea, insomnia, or frequent urination.[17]
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#1. To: Horse, anyone (#0)
Do you know anything about the benefits of white tea? Thanks.
Stronger anti-oxidant properties than green tea; I drink it occasionally.
Thanks - I just learned of it today.
#2. To: Lod (#1)
Do you know anything about the benefits of white tea?
#3. To: Liberator (#2)
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