Pica: are you hungry for the facts?

Pica, the persistent and compulsive ingestion of particular food items or nonnutritive substances, has been associated with iron deficiency, zinc deficiency, geophagia, mental deficiency, developmental delay, and a family history of pica. Nutritional, sensory physiologic, psychosocial, and cultural theories have been advanced to explain this phenomenon, but the etiology of pica is poorly understood. Pica, secondary to iron deficiency, is relatively common and remits after iron therapy. Complications of pica include abdominal problems (sometimes necessitating surgery), lead poisoning, hypokalemia, hyperkalemia, mercury poisoning, phosphorus intoxication, and dental injury. Pica is an underdiagnosed problem that can be caused by a variety of disorders and can lead to serious complications.