Japanese researchers are focusing on saliva as a valuable tool for making diagnoses. A cutting-edge test developed in Japan can detect cancer at a very early stage by analyzing substances in saliva unique to cancerous cells. It requires just a few drops of saliva so it's easy on patients, and doctors are already using it to save lives. Another test offers a quick way to measure people's stress. And we'll share simple massage techniques to encourage saliva secretion for better oral health.