People with the disorder pica compulsively eat items that have no nutritional value. A person with pica might eat relatively harmless items, such as ice. Or they might eat potentially dangerous items, likes flakes of dried paint or pieces of metal.
In the latter case, the disorder can lead to serious consequences, such as lead pisoning.
This disorder occurs most often in children and pregnant women. It’s usually temporary. See your doctor right away if you or your child can’t help but eat nonfood items. Treatment can help you avoid potentially serious side effects.
Pica also occurs in people who have intellectual disabilities. It’s often more severe and long-lasting in people with severe developmental disabilities.
There’s no single cause of pica. In some cases, a deficiency in iron, zinc, or another nutrient may be associated with pica. For example, anemia, usually from iron deficiency, may be the underlying cause of pica in pregnant women.
Your unusual cravings may be a sign that your body is trying to replenish low nutrient levels.
People with certain mental health conditions, such as schizophrenia and obsessive-compulsive disorder (OCD), may develop pica as a coping mechanism.
Some people may even enjoy and crave the textures or flavors of certain nonfood items. In some cultures, eating clay is an accepted behavior. This form of pica is called geophagia.
Dieting and malnourishment can both lead to pica. In these cases, eating nonfood items may help you feel full.
According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), four criteria are required for a diagnosis of pica:
The repeated eating of nonfood substances persists for a period of at least one month.
The eating of nonfood substances is inappropriate to the developmental level of the individual. (Pica cannot be diagnosed in children younger than two because in younger ages, mouthing different kinds of objects is considered normal developmentally.)
The eating behavior is not part of a culturally supported practice.
If the eating behavior occurs in the context of another mental disorder (e.g., intellectual disability, autism spectrum disorder, schizophrenia) or medical condition (including pregnancy), it is sufficiently severe to warrant additional clinical attention.
In previous editions of the DSM, Pica was in the “Disorders Usually First Diagnosed in Infancy, Childhood, or Adolescence.” In the current edition, it was moved into the new combined section, “Feeding and Eating Disorders.” This change reflects the fact that pica can occur in adults as well as children.
If a non-nutritive substance is eaten to suppress appetite in an individual with anorexia nervosa, a diagnosis of pica would not be made. Some people with avoidant/restrictive food intake disorder (ARFID), especially those whose selective eating is based on the sensory aspects of food may also have pica.
These individuals are very sensitive to texture and may seek out nonnutritive substances with a preferred texture. Pica can also occur with nonsuicidal self-harm in cases in which foreign objects are swallowed.
Due to extremely limited research on pica, risk factors are not well-understood. One popular theory is that mineral deficiencies, in particular iron deficiency, can cause pica and that pica is the behavioral response to the deficiency.
Much of the evidence comes from case reports that showed a cessation of the behavior after correction of the deficiency.Some have proposed that pica may develop in response to stress on top of a dietary deficiency.
Pica can be associated with significant medical risks depending on the substances ingested and how severe the behavior is.
Heavy metals such as lead, mercury (from paper), zinc, and copper can be toxic. Pica can lead to masses of consumed matter in the stomach and gastrointestinal tract, blockages in the intestines, and tears requiring surgery.
Pica can also lead to issues including internal parasites, poisoning, choking, respiratory problems, and death.
There is no widely-accepted treatment for pica. Current interventions to address pica include surgery as well as nutritional, pharmacological, and behavioral treatments. Surgical interventions may be required when items ingested have caused damage to the body, but they do not address the underlying symptoms.
Nutritional supplements such as iron have been used for treatment when underlying nutritional deficiencies or excesses have been identified. Various medications have been tried although there are no conclusive studies on their use. There are limited studies of behavioral interventions for pica.
Interventions that seem most likely to be successful in treating pica in children are combination treatments that include reinforcement procedures such as contingent reinforcement and discrimination training.
- Contingent reinforcement strategies reward children with food or toys when they do not engage in pica behaviors.
- Discrimination training strategies involve teaching children to distinguish between edible and inedible substances and also about the dangers of eating inedible items.
For adults with pica, cognitive behavioral therapy (CBT) may be a useful technique. Such treatment may focus on helping the person to change their thoughts about eating the nonfood item and changing the behavior and replacing it with another coping strategy.
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