Archaeological evidence suggests that tea leaves dipped in boiling water were consumed 500,000 years ago. Botanical evidence indicates that India and China were among the first countries to grow tea
Green tea contains polyphenols that protect against certain cancers and are also powerful antioxidants. These antioxidants have been shown to be very beneficial to the heart by helping to prevent the oxidation of LDL cholesterol.
There are four primary polyphenols in green tea, often collectively called catechins. They are powerful antioxidants, and recent studies have shown that they fight viruses, slow down aging and have a beneficial effect on health.
Most of the initial evidence that green tea is anti-carcinogenic is based on epidemiological studies that show lower rates of many types of cancer among populations such as Japan and China who drink green tea as part of 39, daily cultural habits.
Clinical tests have shown that green tea catechins destroy free radicals, highly reactive molecules and fragments of molecules that can damage the body at the cellular level, making it vulnerable to cancer, heart disease and many other degenerative diseases. on green tea extracts yielded impressive results, identifying polyphenol (-) – epigallocatechin gallate (EGCG) as a responsible component. The EGCG is able to force certain cancer cells into a situation in which they have to die or be killed as part of a process called "apoptosis". Other evidence shows that EGCG has an inhibitory effect on the enzyme, urokinase, necessary for tumor formation, thus preventing the formation of tumors.
It has been shown that (EGCG), an antioxidant found in green tea, is at least 100 times more effective than vitamin C and 25 times more effective than vitamin E in protecting cells and DNA from damage that we could associate with cancer, disease and other serious illnesses. This antioxidant has double the benefits of resveratrol, found in red wine.
The only possible side effect of green tea is possible insomnia because it contains caffeine. Its caffeine content is, however, much lower than that of coffee.