Pica is a medical disorder characterized by an appetite for substances largely non-nutritive (e.g. metal [coins, etc.], clay, coal, soil, feces, chalk, paper, soap, mucus, ash, gum, etc.) or an abnormal appetite for some things that may be considered foods, such as food ingredients (e.g. flour, raw potato, raw rice, starch, ice cubes, salt). In order for these actions to be considered pica, they must persist for more than one month at an age where eating such objects is considered developmentally inappropriate. The condition's name comes from the Latin word for magpie, a bird that is reputed to eat almost anything. Pica is seen in all ages, particularly in pregnant women, small children, and those with developmental disabilities.
Pica in children, while common (usually only in young children or children with autism or another mental or developmental disorder), may be dangerous. Children eating painted plaster containing lead may suffer brain damage from lead poisoning. There is a similar risk from eating dirt near roads that existed prior to the phaseout of tetra-ethyl lead in gasoline (in some countries) or prior to the cessation of the use of contaminated oil (either used, or containing toxic PCBs or dioxin) to settle dust. In addition to poisoning, there is also a much greater risk of gastro-intestinal obstruction or tearing in the stomach. This is also true in animals. Another risk of dirt-eating is the possible ingestion of animal feces and accompanying parasites. Pica can also be found in animals, and is most commonly found in dogs.
The scant research that has been done on the causes of pica suggests that the disorder is a specific appetite caused by mineral deficiency in many cases, in females named typically iron deficiency, which sometimes is a result of celiac disease. Often the substance eaten by someone with pica contains the mineral in which that individual is deficient. More recently, cases of pica have been tied to the obsessive–compulsive spectrum, and there is a move to consider OCD in the etiology of pica; however, pica is currently recognized as a mental disorder by the widely used Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). Sensory, physiological, cultural, and psychosocial perspectives have also been used by some to explain the causation of pica.
Mental health conditions, such as obsessive-compulsive disorder (OCD) and schizophrenia can sometimes cause pica. It was suggested that stress associated with traumatic events is linked to pica disorder. Some of the traumatic events common in individuals with pica include maternal deprivation, parental separation or neglect, child abuse, disorganized family structure and poor parent-child interaction. Pica may also be a symptom of iron deficiency anemia secondary to hookworm infection.
However, pica can also be a cultural practice not associated with a deficiency or disorder. Ingestion of kaolin (white dirt) among African-American women in the U.S. state of Georgia shows the practice there to be a DSM-IV "culture-bound syndrome" and "not selectively associated with other psychopathology". Similar kaolin ingestion is also widespread in parts of Africa. Such practices might stem from health benefits such as clay's ability to absorb plant toxins and protect against toxic alkaloids and tannic acids.
Unlike in humans, pica in dogs or cats may be a sign of immune-mediated hemolytic anemia, especially when it involves eating substances such as tile grout, concrete dust, and sand. Dogs exhibiting this form of pica should be tested for anemia with a CBC or at least hematocrit levels.
ccompanying parasites. Pica can also be found in animals, and is most commonly found in dogs.