Green tea, which is made from the leaves of the Camellia sinensis plant, is believed by many scientists and complementary health practitioners to have health benefits. The property in green tea that is thought to provide health benefits is called polyphenol. This powerful antioxidant neutralizes free radicals, which are damaging compounds in the body brought on by a variety of natural and environmental factors. Green tea is made using unfermented leaves, which provide a high concentration of polyphenols. Other teas such as black and oolong use fermented and partially fermented leaves, so the health benefits are not thought to be as great.
The connection between green tea and health dates to ancient China and India. Green tea traditionally was used to promote a healthier heart and sharper brain. It also was used as a diuretic, as an astringent, to reduce flatulence and to control blood sugar, among other things. In more recent times, extensive human, animal and laboratory studies have shown a connection between green tea and health in relation to a host of diseases, including cancer, diabetes, atherosclerosis and other serious illnesses. Other maladies that are thought to be helped by green tea are Crohn's disease, ulcerative colitis and liver disease.
Green tea and health benefits have been studied for a variety of cancers, and various conclusions have been reached. Some studies have indicated that the polyphenol in green tea might reduce the risk of some cancers or slow its advance, and other studies showed no benefits for treating the same cancers. Studies for some cancers show conflicting results, such as for esophageal cancer, as an example, and different studies have shown that green tea consumption can either prevent or cause cancer. A few of the other cancers that have been studied in connection with green tea include breast cancer, skin cancer, pancreatic cancer and stomach cancer.
Green tea also is popular as a weight loss supplement. Studies have shown that green tea extract might help burn fat by boosting metabolism. Green tea and health links have been made in a variety of other areas too, including reducing symptoms from the common cold and flu.
Drinking green tea is a popular way to gain its health benefits. Green tea also is available in pill and capsule forms. Before starting a green tea program for health, it is a good idea to speak with an expert about possible interactions with other supplements and medications. People with certain diseases and conditions shouldn’t drink tea, and a medical professional will be able to determine whether a person should consume green tea.