Stress is killing us, according to scientists, and a new National Geographic special exploring the latest research on how and why features Stanford neuroscientist Robert Sapolsky, who has spent decades studying stress in humans and baboons.

"Stress: Portrait of a Killer," a co-production of National Geographic and Stanford University, is scheduled to premier Sept. 24 on PBS and be broadcast throughout the fall.

Sapolsky, who holds the John A. and Cynthia Fry Gunn Professorship, is particularly interested in how social standing makes one more or less susceptible to stress, and he has found some striking parallels between us and our fellow primates.

Sapolsky is part of a group of researchers appearing in the program, whose collective work is illuminating just how big an impact stress has on our health. The documentary is based partly on Sapolsky's best-selling book Why Zebras Don't Get Ulcers.

The broadcast represents the first time National Geographic has joined forces with a major research university to create original programming in the areas of science and technology for television audiences. Randy Bean of Stanford served as an executive producer.

For more information and video interviews with Robert Sapolsky, please visit the Killer Stress website.