Japanese green tea has been spreaded and loved in the world. Its extract called Catechin in the tea is very effective to prevent dementia, diabete, and many other symtoms. Many benefits by drinking green tea are often called a secret of Japanese long life. Green tea is divided into Gyokuro, the best quality tea, Maccha, the powdered tea leaf mixed with boiled water, and the others. Green tea contains some caffeine but there's caffeine-less green tea available.