Tea is a tropical and subtropical plant which is scientifically known as Camellia Sinensis. From approximately 3000 types of tea result of crossbreeding, we got three types of tea result of the process, namely green tea, oolong tea and black tea. Tea processing mode that is by chopping the tea leaves and dried in the sun so that chemical changes before being dried. The treatment will cause leaves to brown color and gives the taste of black tea which is typical.

Green tea is the oldest type of tea, well liked by the community, especially Japan and China. Here the tea leaves have a bit of cooking, heating and drying so that only green leaf color can be maintained. While oolong tea is more of a transitional type between black tea and green tea. The three types of tea each with its own health because they contain binding properties of biochemical called polyfenol, including flavonoids. Flavonoids are a group of antioxidants that exist naturally in vegetables, fruits, and beverages such as tea and wine.

Subklas polyphenols including flavonols, flavones, flavanone, anthocyanidins, seem, catechin, and biflavan. Derivatives of catechins such as epi-cathecin (EC), epigallo-cathecin (EGC), cathecin epigallo-gallate (EGCG), and quercetin is mainly found in tea. EGCG and quercetin is a powerful anti-oxidant with a power of up to 4-5 times higher than vitamin E and C, which is also a potential antioxidant. Antioxidants are known to be able to prevent cells from damage considering each cell damage would contribute more than 50 diseases.

Green tea contains EGCG, as well as black tea, said a biochemist. In a study by Dutch researchers say, consume 4-5 cups of black tea every day cut the risk of stroke by 70% compared with those who consumed two cups of tea a day or less. Other reports mention more consuming black tea is associated with low heart attack cases. John Folts, director of the Medical School, the Central Artery Thrombosis Research and Prevention, University of Wisconsin, the U.S. found the key properties of flavonoids in tea. Research results show that flavonoids in black tea could inhibit the clotting of blood platelet cells, thereby preventing blockage of blood vessels in hantung coronary disease and stroke. Another study mentioned that fanatical tea drinkers had higher levels of cholesterol and low blood pressure, although it remains unclear whether it was directly caused by tea.

Researchers at Case Western Reserve University, Cleveland, USA to find the effect of the use of green tea on the skin up to 90%. It turned out that tea is very effective to protect the skin from the sun that can cause skin cancer. Tea also contains fluoride which is known to strengthen tooth enamel and helps prevent tooth decay. In a laboratory study in Japan, researchers found that tea helps prevent formation of dental plaque and kill bacteria cause inflammation of the gums mouth.

Japanese study shows, pendudukanya tea producing region known as fanatic tea drinker, very low death rate caused by cancer. Results of another study, carried out cooperation between the research team Oguni and cancer research center in Beijing to study the effects of green tea extract on mice that had been given food rations carcinogenic (cancer trigger substances). Reportedly, the average rate of cancer in rats that received green tea extract half of the mice who did not receive green tea extract.

The researchers believe that polyphenols known as cathecin contained in green tea, helps the human body fight cancer cells. Another study conducted by Oguni and Dr. Masami Yamada from Hamamatsu Medical Center found cathecin kill Helicobator pylori, the bacteria trigger gastric cancer.