he amount of sleep you need varies with age, but, for most adults, it's seven to eight hours a night. Many of people don't get that much, and that can have serious consequences. On the next Mayo Clinic Radio, sleep medicine specialist Dr. Timothy Morgenthaler explains why getting adequate sleep is so important for good health. Also, infectious disease specialist Dr. Stacey Rizza has an update on tuberculosis. March 24 is World TB Day. And, pathologist Dr. Bobbi Pritt has the latest on a new bacterium that causes Lyme disease and how to protect against it.