Why Zebras Don't Get Ulcers is a 1994 (2ed 1998, 3ed 2004) book by Stanford University biologist Robert M. Sapolsky. The book proclaims itself as a "Guide to Stress, Stress-Related Diseases, and Coping" on the front cover of its third and most recent edition. The name stems from Sapolsky's insistence that wild animals are less susceptible than humans to stress-related disorders such as ulcers, hypertension, decreased neurogenesis and increased hippocampal neuronal atrophy.
Sapolsky focuses on the effects of glucocorticoids on the human body, stating that such hormones may be useful to animals in the wild escaping their predators, but the effects on humans, when secreted at high quantities or over long periods of time, are much less desired. Sapolsky relates the history of endocrinology, how the field reacted at times of discovery, and how it has changed through the years. While most of the book focuses on the biological machinery of the body, the last chapter of the book focuses on self-help.