|
Different Types Of Tea Bags
|
Tea leaves contain more than 700 chemicals, among which the compounds closely related to human health are flavanoids, amino acids, vitamins (C, E and K), caffeine and polysaccharides. Moreover, tea drinking has recently proven to be associated with cell-mediated immune function of the human body. Tea plays an important role in improving beneficial intestinal microflora, as well as providing immunity against intestinal disorders and in protecting cell membranes from oxidative damage. Tea also prevents dental caries due to the presence of fluorine. The role of tea is well established in normalizing blood pressure, lipid depressing activity, prevention of coronary heart diseases and diabetes by reducing the blood-glucose activity. Tea also possesses germicidal and germistatic activities against various gram-positive and gram negative human pathogenic bacteria. Both green and black tea infusions contain a number of antioxidants, mainly catechins that have anti-carcinogenic, anti-mutagenic and anti-tumoric properties.
In a large study of over 11,000 Scottish men and women completed in 1993 and published in the 1999 Journal of Epidemiology and Community Health (1999, pp. 481–487), there was an increase in the risk of coronary disease with the regular consumption of tea, although it disappeared after adjustment for confounding factors (age and occupational status).
The IARC list teas as under Group 3 carcinogens since injection of black tea concentrates under the skins of mice showed some cancerous growths. However, it has not been possible to prove that tea affects humans in similar ways through consumption.
Consumption of some forms of tea has the potential to result in acute liver damage in some individuals. Several herbal and dietary supplements have been linked to liver damage, caused in part or completely by the presence of green tea extract in these supplements; the most notable cases include Hydroxycut (415 mg of a mixture of green, white, and oolong tea extracts, and several other herbal extracts, per dose); Exolise (360 mg of green tea extract per dose); and Tealine (250 mg of green tea extract per dose). These concerns resulted in withdrawals of the first two products and a class action lawsuit against the manufacturer of Hydroxycut. The risk is thought to be quite small: in case of Hydroxycut, 9 million bottles were sold in the U.S. over the lifetime of the product, resulting in 23 known severe cases, however, these included at least one fatality and at least three cases of liver failure resulting in a liver transplantation. In case of Exolise, the risk of an adverse effect was estimated as less than 1 per 100,000.
|
|