References:
The Green Tea Book: China's Fountain of Youth By Lester A. Mitscher, Victoria Dolby, Victoria Dolby Toews
http://arthritis.about.com/od/preventionandriskfactors/a/greentea.htm
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Green tea dietary supplements are sold in capsule form. Liquid extracts made from the leaves and leaf buds are also available. Standardized formulations are preferred because they provide a more reliable dose.
Green tea supplements must be used as directed on the package or as recommended by your doctor or other health care provider.
As a widely consumed beverage, green tea is generally regarded as safe. It does contain caffeine, at perhaps a slightly lower level than black tea, and can therefore cause insomnia, nervousness, and the other well-known symptoms of excess caffeine intake.
Green tea extracts, however, may not be safe. There are a growing number of case reports in which use of a concentrated green tea extract was associated with liver inflammation. 1 In most cases, liver problems disappeared after the extract was discontinued. But, in two cases, permanent liver failure ensued requiring liver transplantation. 2 While it is not absolutely certain that the green tea extract causedthe liver problems, nor how it might do so, these reports do raise significant concerns about use of green tea extracts, especially by those with liver disease or prone to it.
Green tea should not be given to infants and young children. There are theoretical concerns that high dosages of EGCG might be unsafe for pregnant women. 3 Dried green tea leaf contains significant levels of vitamin K on a per-weight basis. On this basis, it has been stated that people using blood thinners in the warfarin (Coumadin) family should avoid green tea, because vitamin K antagonizes the effect of those drugs. However green tea taken as a beverageprovides such small amounts of the vitamin that the risk seems minimal for normal consumption. There is one case report of problems that developed in a person on warfarin who consumed as much as a gallon of green tea daily. 4
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Findings of a study reported in the Proceedings of the National Academy of Sciences suggest that antioxidants found in green tea may help prevent or reduce the severity of arthritis. This was done by a team of researchers from Case Western Reserve University in Cleveland, Ohio. For this study, the investigators used mice to investigate the effects of polyphenols in rheumatoid arthritis. The mice were given either water or water enriched with green tea. The dosages given to the subjects were comparable to human daily consumption of four cups of green tea. To induce arthritis, the mice were injected with collagen. The researchers found out that mice which were given green tea polyphenols were less susceptible to developing collagen-induced arthritis than the mice in the placebo group. Although the mice fed green tea also developed arthritis, it was late onset and mild. Out of 18 mice that received green tea polyphenols, 8 developed arthritis. On the other hand, 17 out of 18 mice that were fed plain water developed arthritis. Moreover, joint tissue examination also showed that the subjects who received green tea had marginal infiltration of joint cells, while those who were given placebo had massive infiltration.
Green tea has been reported to have antimicrobial, antioxidant, immune-boosting and anti-inflammatory properties. It is made from the dried leaves of a perennial shrub known as Camellia sinensis. The use of green tea dates back to about 5,000 years ago. Green tea may have health benefits which include preventing the incidence and severity of rheumatoid arthritis.
Green tea has a long history of therapeutic use. Since ancient times, it has been valued as a traditional tonic for keeping the body in good condition. Today, scientific studies have confirmed the traditionally held benefits of green tea.
Green tea has been extensively studied and in addition to effectively treating arthritis, research suggests that green tea may be useful for the following health conditions:
Green tea is made from unfermented leaves which are though to have the highest concentration of powerful antioxidants called polyphenols. Antioxidants are substances that scavenge the damaging compounds in the body which are called free radicals. These compounds are known to tamper with the cell's genetic material and may even cause cell death. Many experts believe that free radicals contribute to aging and the development of a health problems such as cancer and heart disease. The polyphenols in green tea can neutralize free radicals. Research show that polyphenols may benefit patients with rheumatoid arthritis.