Drink green tea tea when it's freshly made but slightly cooled. Scalding tea can damage your digestive system. Moreover, recent studies suggest that too much hot tea can promote throat cancer.[1] Conversely, compounds in tea like catechins, theanine, and vitamins C and B diminish over time through oxidation, so the health benefits are strongest with fresh tea. Old tea can also harbor bacteria, especially since its antibacterial properties diminish with time.[2]