Green tea is made solely from the leaves of Camellia sinensis that have undergone minimal oxidation during processing. Green tea originates in China and has become associated with many cultures throughout Asia. It has recently become more widespread in the West, where black tea is traditionally consumed.
Ingestion of large amounts of tea may cause nutritional and other problems because of the strong binding activities of tea polyphenols and the caffeine content, although no solid data exist concerning harmful effects of tea consumption.
Modern studies in both Asia and the West have provided encouraging results indicating that drinking green tea contributes to fighting many different kinds of cancers including stomach, oesophageal, ovarian and colon.
Green tea contains an especially high amount of antioxidants—in particular, a type of polyphenol called a catechin, the most active and abundant of which is epigallocatechin-3-gallate (EGCG).
Green tea's antioxidant properties appear to help protect the liver from some conditions. The University of Maryland suggests that drinking about 10 cups of green tea daily can reduce the chances of liver disorders in men. The university also claims that several tests link the substance catechin found in green tea with the ability to decrease liver swelling from viral hepatitis.
"Green tea is made solely from Camellia sineneis leaves that have undergone a process of minimal oxidation. Even though the actual weight loss will not likely be extremely significant, and not immediate, the polyphenols and caffeine in green tea have been shown to boost one’s metabolic rate. In addition, it does it without increasing heart rate, which makes is safe even for people with elevated blood pressure."
Ancient Chinese people knew the benefits of green tea for health. They have always used it for medical purposes. However, in Ancient China, it was used especially against the headaches and depression.
Green tea caffeine taken in proper quantity stimulates every organ in the body and clears your mind. The small amount of caffeine (about 9 mgs of caffeine) present in a normal serving of green tea can stimulate the skeletal muscles and smooth the progress of muscular contraction.
The National Cancer Center Research Institute in Tokyo suggests that "Drinking tea may be one of the most practical methods of cancer prevention available at present".*
Unlike black and oolong tea leaves, which are fermented, green tea leaves are steamed, leaving a higher concentration of antioxidants, called polyphenols. These antioxidants are why green tea is widely promoted for its health benefits.
Thanks to the way it is processed, green tea retains a high concentration of antioxidants that give the beverage a wide range of health benefits.