In a study by the American Health Foundation published in Food and Chemical Toxicology 40 (2002) Tea was found to have chemopreventive effects through its antioxidants, detoxifying enzymes, and effects on cellular growth and natural cellular death (apoptosis) the opposite of cancerous cell growth.
Tea has been found to kill Helicobacter pylori which causes ulcers and stomach cancer as well as inhibiting the effects of tobacco use in the oral cavity, esophagus, and lung. They conclude that the use of "a widely available, tasty, inexpensive beverate, tea, has displayed valuable preventitive properties in chronic human diseases."
In addition, tea is a natural bronchodilator and anti-inflammatory for the lung tissue, allowing otherwise struggling cells to recover. Its effects on the lungs have already been noted in a previous section