Pica is a pattern of eating non-food materials, such as paper, clay, metal, chalk, soil, glass, or sand. The cravings found in patients diagnosed with pica may be associated with a nutritional deficiency state, such as iron-deficiency anemia; with pregnancy; or with mental retardation or mental illness. The word pica is derived from the Latin word for magpie, a species of bird that feeds on whatever it encounters. Pica is more commonly seen in women and children, where it affects people of all ages in these subgroups. Particularly it is seen in pregnant women, small children, and those with developmental disabilities such as autism.
There is no single cause of pica. In some cases, a deficiency in iron, zinc, or another nutrient may lead to pica. The body will attempt to replace these elements through “food.” Anemia or iron deficiency may be the underlying cause of pica in pregnant women.
Individuals with certain mental issues, such as schizophrenia and obsessive-compulsive disorder may develop pica as a coping mechanism.
Some people may enjoy and crave the textures or flavors of certain nonfood items. In some cultures, eating clay a form of pica called geophagia is an accepted behavior.
Dieting and malnourishment can both lead to pica. In these cases, eating non-food items can lead the sufferer to feel full.
Infants and children diagnosed with pica commonly eat paint, plaster, string, hair, and cloth. Older children may eat animal droppings, sand, insects, leaves, pebbles and cigarette butts. Adolescents and adults most often ingest clay or soil.
The symptoms of pica vary with the item ingested.
- Sand or soil is associated with gastric pain and occasional bleeding.
- Chewing ice may cause abnormal wear on teeth.
- Eating clay may cause constipation.
- Swallowing metal objects may lead to bowel perforation.
- Eating fecal material often leads to such infectious diseases as toxocariasis, toxoplasmosis, and trichuriasis.
- Consuming lead can lead to kidney damage and mental retardation.
If pica is suspected, a medical evaluation is important to assess for possible anemia, intestinal blockages, or potential toxicity from ingested substances. If symptoms are present, the doctor will begin an evaluation by performing a complete medical history and physical exam. The doctor may use certain tests such as X-rays and blood tests to check for anemia and look for toxins and other substances in the blood, and to check for blockages in the intestinal tract. The doctor also may test for possible infections caused by eating items contaminated with bacteria or other organisms. A review of the person’s eating habits also may be conducted.
Before making a diagnosis of pica, the doctor will evaluate the presence of other disorders such as mental retardation, developmental disabilities, or obsessive-compulsive disorder as the cause of the odd eating behavior. This pattern of behavior must last at least one month for a diagnosis of pica to be made.
Pica frequently ends spontaneously in young children and pregnant women. Untreated pica, however, may persist for years, especially in persons with mental retardation and developmental disabilities.