Pica

Pica is an eating disorder (ICD-10: WHO International Classification of Diseases) in which a person repeatedly eats non-food items. The exact cause of pica is often unknown. It's considered normal for children younger than 18 to 24 months old to put things in their mouths. After this age, eating non-food items is thought to be abnormal. Some people are more likely to have pica: children older than 24 months, pregnant women, especially in rural areas, persons with mental retardation, people with severe psychological problems, people with zinc or iron deficiency.