Craving Earth: Understanding Pica—the Urge to Eat Clay, Starch, Ice, and Chalk

Humans have eaten earth, on purpose, for more than 2,000 years. They also crave starch, ice, chalk, and other unorthodox food items. Some even claim they are "addicted" and "go crazy" without these items. Sifting through extensive historical, ethnographic, and biomedical findings, Sera L. Young creates a portrait of pica, or nonfood cravings, from humans' earliest ingestions to current trends and practices. In engaging detail, she describes the substances most frequently consumed and the many methods used to obtain them. She reveals how pica is remarkably prevalent, identifies its most avid partakers, and describes the potentially healthful and harmful effects. She evaluates the many hypotheses about the causes of pica, from the fantastical to the scientific, including hunger, nutritional deficiencies, and protective capacities. Never has a book examined pica so thoroughly or accessibly, merging absorbing history with intimate case studies to illuminate a behavior deeply entwined with human biology and culture.