Green tea is considered to be the healthiest beverage on the planet. - Tea leaves are harvested and then quickly heated and dried to prevent too much oxidation. - The oxidation process would turn the green leaves brown and alter their fresh-picked flavor. - All teas are made of leaves from the Camellia sinensis. The Camellia sinensis sinensis is a small-leaved plant native to China and is commonly used for green and white teas. The Camellia sinensis assamica is a larger-leaved plant typically used for black and oolong teas. Most green tea should be quite light in color, typically green, yellow or light brown.