Green teas make up more than 70 percent of Chinese tea production, and are the most widely sipped tea in the world. Green tea is usually picked with the bud and one or two leaves, after which it is immediately laid out to wither, and then heated. The heating process eliminates the enzymes in the leaves that cause oxidation and allows the polyphenols in the leaves to be released. After being heated, the leaves are rolled to break down their cell structure and release their aromatic oils. They are also given their final shape, which is twisted, flat, needle-shaped or bead-shaped. The shaping of the leaves can either be done by hand or mechanically, depending on where the tea is being processed. Finally, the leaves are left to dry once more, which stabilizes their aromatic oils before their final sifting. Green tea often has a somewhat grassy, floral flavor. It is high in antioxidants and has been said to help regulate cholesterol and blood sugar.