Episode 12: Are you getting enough sleep? by Harvard University published on 2012-06-27T13:50:39Z According to research by Elizabeth Klerman, an associate professor of medicine at Harvard Medical School and Brigham and Women's Hospital, most adults should be getting 8.5 to 9 hours of sleep each night. Learn about her study and about the benefits of a good night's sleep. Plus, HMS Associate Professor of Medicine Julia Wang explores what causes the immune system to attack healthy cells and tissues by mistake. Harvard Medical School Office of Communications and External Relations. May 23, 2011. Copyright 2012 The President and Fellows of Harvard College.