During the developmental stages of childhood, it is normal for most children to explore their surroundings by tasting or ingesting any number of non-food items. When the compulsion to ingest non-nutritive substances lasts a month or longer, or persists after the age of two, an individual may be suffering from an eating disorder known as pica. This condition is characterized by overwhelming and persistent cravings to consume items other than food.
Pica most commonly affects children and pregnant women. The condition seems to be most prevalent in children who are developmentally disabled. In addition, it occurs much more frequently in developing countries and rural areas.
While very little research has been conducted on the causes of pica, some studies suggest that the cravings for non-food items may stem from malnutrition. This is most probable in areas where food is scarce. Most pregnant women with pica develop cravings for gritty substances such as soil, suggesting that they may be suffering from mineral deficiencies.
While some instances of pica may develop due to nutritional problems, others seem to stem from pathological factors. For example, the condition may develop as a response to environmental stress, such as child abuse. Some researchers have suggested that pica in patients with mental retardation is caused by an inability to distinguish between food and non-food items. However, this hypothesis is refuted by evidence that mentally disabled individuals with the condition seem to show a strong preference for non-food substances.
People suffering from pica most commonly crave earthy, gritty substances, such as soil, chalk, paper or earthenware. In some instances, patients may ingest items that are considered food ingredients, such as flour, baking soda or coffee grounds. In rarer cases, individuals have been known to crave human substances, such as blood, hair, urine or their own body parts.
Untreated, pica can cause a large number of health problems. Most notably, patients are at a high risk for ingesting poisonous substances. For example, it is not uncommon for people with with this condition to experience lead poisoning. In addition, patients may develop mild to severe disruption of the gastro-intestinal tract, ranging from constipation to life-threatening intestinal blockage.
Treatment for pica varies depending on the individual case and the medical professional who is treating it. In many cases, treatment is predominantly psychological. Aversion therapy has been very effective in re-training patients with pica to overcome their cravings. Cases that are a result of mineral deficiencies can be counteracted by improving the diet of the patient. In cases where is caused by developmental or psychological problems, medication may also prove effective in reducing cravings for non-food items.