Pica is a psychological disorder characterized by the persistent craving and consumption of non-food items. Individuals with pica may eat substances such as dirt, chalk, paper, or even hair. This behavior can occur in people of all ages but is more commonly observed in children and pregnant women. The causes of pica can vary and may include nutritional deficiencies, stress, or developmental disorders. It is important for those exhibiting pica to seek medical advice, as consuming non-food items can lead to serious health complications, including gastrointestinal blockages or poisoning.