'Its liquor is like the sweetest dew from Heaven,' said Lu Yu in the eighth century classic, 'The Classic of Tea' (trans. F. Carpenter.) The Chinese have been using green tea as a medicine for at least four thousand years. Recently the health benefits of this soothing drink have also been heavily promoted in the West. These may include reducing high blood pressure, boosting the immune system, lowering high cholesterol, and even helping to prevent cancer.