pica

pica, mental health condition, a type of eating disorder, characterized by the compulsive eating of substances that are not food and that have little or no nutritional value. For many people with the condition, pica is short-term and benign, but for some people it is a lifelong condition, and it can be dangerous if hazardous items are ingested. It occurs in people of all ages from 24 months on but may be more prevalent in children under six years of age, pregnant people, persons with developmental disabilities, and people with certain other mental health conditions, including autism spectrum disorder (ASD) and schizophrenia. The disorder is named after the Eurasian magpie (Pica pica), a bird species that sometimes eats nonfood items.

The nonfood items most commonly eaten by people who have pica include ice (known as pagophagia), soil or clay (known as geophagia), chalk, charcoal, paint chips, human or animal feces, hair (known as trichophagia), coffee grounds, eggshells, raw starch (known as amylophagia), paper, pebbles, soap, and cloth. In some cultures, geophagia—especially eating clay—as a medicinal practice is culturally supported and socially normative. Others who live with poverty and famine may engage in geophagia to ease hunger pangs and to provide needed micronutrients, such as iron or calcium.

Causes and risk factors

Scientists and physicians are not exactly sure what causes pica. Some people with the disorder have nutritional deficiencies, such as iron deficiency anemia, but, besides such deficiencies, direct causes of the disorder have yet to be established. Pica studies have used different definitions of the disorder, and underreporting is common among affected subjects, making it difficult to draw scientifically accurate conclusions. Some studies have found associations with psychological factors such as stress, anxiety, and child neglect or abuse.

The dangers of pica depend on the types of objects people consume. Ice, for example, is usually harmless, but excessively chewing it can damage teeth. Soil, clay, and feces may contain parasites and harmful bacteria. Paint chips may contain lead, which is a poisonous substance. Hair may become lodged in a person’s throat, stomach, or intestines, causing choking or blockages. Sharp objects may damage the digestive system.

Treatment and care

For those diagnosed with pica during pregnancy, the condition usually ceases after giving birth. For children with the diagnosis, the condition usually eases as they grow older. For others, however, the consumption of nonfood items may be lifelong and difficult to control. In addition, it may occur in tandem with other disorders, such as obsessive-compulsive disorder (OCD), schizophrenia, or trichotillomania (a compulsion to pull out one’s own hair).

There are no lab tests for pica itself, so diagnosis may occur only after symptoms, such as damaged teeth, appear or after people inform a physician about it. However, many people who have pica feel embarrassed by or ashamed of their condition, so they may not inform a physician when they have symptoms. Diagnosis of the disorder may involve running tests to detect infections, poisoning, or electrolyte imbalances or using imaging techniques, such as X-rays, ultrasound, or magnetic resonance imaging (MRI), to look for signs of blockages or damage in the digestive system. Counseling and treatment emphasizing a healthy diet may ease pica symptoms or cause the condition to cease.