Why Zebras Don’t Get Ulcers

The contrast between zebras and people anchors the account of stress by Stanford biologist Robert M. Sapolsky: for a zebra, stress is generally episodic, such as running from a lion, while for people it is often chronic, such as worrying about losing a job. The human body switches on the same physiological responses as an animal's, but people rarely settle conflicts by fighting or fleeing, and over time that activation makes them ill. Sapolsky examines how prolonged stress causes or worsens depression, ulcers, colitis and heart disease, how social conditions such as poverty raise the risk of disease, and how stress responses can be controlled. This third edition adds chapters on sleep and addiction.

Oliver Sacks praised Sapolsky as one of the finest science writers of his time.