Pica eating disorder is a disorder that is characterized by a persistent appetite for non-nutritive materials. That doesn’t mean junk foods, it means things that aren’t ‘foods’ at all. For instance metal, clay, sand, soil, feces, chalk, ink, pencil, batteries, soap, mucus, lipstick and more.

In young children this ‘curiosity’ is considered a normal part of development, and strange appetites can also be symptomatic of other conditions. For problem to be classified as a pica eating disorder then it must persist for over a month and occur at an older age. Interestingly the word ‘pica’ comes from the Latin for magpie – because magpies are renowned for their tendency to eat anything they find.

Pica is most common in women and children, and particularly those with developmental disorders. However it can also occur in otherwise psychologically ‘normal’ individuals and is sometimes characterized as a type of obsessive compulsive disorder – though causes vary and classification is disputed.

Risks

Of course pica eating disorders can be dangerous as it can lead to the ingestion of harmful toxins and substances. For instance it can result in lead poisoning, mercury poisoning, overdose and bacteria. Even if the substance is not harmful in itself, it may contain other contaminants such as pesticides, bacteria or even feces and this can cause poisoning, infection or parasites.

At the same time even when the substance is clean and not harmful, it can still result in gastrointestinal conditions and indigestion and even constipation. Choking is also a risk and particularly in young children.

Causes

The research surrounding pica eating disorder is limited. However it has been suggested that the disorder might be caused by dietary problems. For instance a mineral deficiency such as an iron deficiency could result in the consumption of metals and other alien substances. It may be that the substance consumed holds clues to the nature of the deficiency – for instance someone eating dirt might be lacking vitamin B12, while someone consuming iron might lack iron. Generally our body tries to inform us when something is missing from our diet and our cravings are designed to ensure that we eat the right things – however in our modern lifestyles our immune systems are not prepared for these natural sources and sometimes we can mix up the signals our body is sending us. In other cases it could be caused by the existence of parasites such as hookworm which exist in our stomach and cause unusual cravings.

It might also be caused by psychological conditions. In the case of conditions such as autism it can be caused by curiosity, or a result of self harm and repetitive behavior. Consumption of any substance can result in a dopaminergic effect causing the release of reward chemicals and that can make it addictive. In other research it has been linked to obsessive compulsive disorder – here damaging thoughts convince the individuals that they ‘must’ consume these substances and treatments such as ‘CBT’ (Cognitive Behavioral Therapy) may help to ‘correct’ these thought processes. A psychodynamic analysis of the condition might suggest that this could be a cry for help, or a conscious expression of an unconscious anxiety. Stress and depression have been shown to be risk factors in pica.

It could also conceivably be caused by anorexia nervosa – some anorexic individuals have been known to consume substances such as cotton wool in order to create the sensation of being full and to quell hunger without absorbing any calories.

Note: Interestingly, behaviors similar to pica eating disorders have been observed as a part of some foreign cultures. For instance African-American women in the state of Georgia often practice the consumption of white dirt (kaolin) and show no other psychopathology. Interestingly though kaolin has some benefits due to its ability to absorb alkaloids and tannic acids.

Treatment

Treatment of pica eating disorder will vary greatly depending on the case and the suspected cause. In instances where there is an underlying deficiency this of course can be treated through diet changes, injections or supplementation. Often dogs will eat concrete and grout and this is such an example which can be treated with iron supplementation. Zinc in particular has shown to help treat cases of pica even when there is no deficiency.

In cases where the problem is psychological then treatments such as CBT can help to treat obsessive compulsive causes. This will involve identifying negative thought patterns that might be leading to the problem and replacing them with positive thoughts and phrases. Alternatively other forms of therapy such as psychotherapy might help to address underlying stresses and conflicts that result in this destructive behavior. Patients can also have some success in trying to replace their behaviors with less damaging ones – such as chewing gum or exercising. This can cause the same dopamine release and also help to satisfy an oral fixation.

As a last resort for psychological causes, medication might be successful in treating the problem. SSRIs (selective serotonin re-uptake inhibitors) for instance have been shown to be effective though have some side effects of their own. In the case of developmental issues, restraint is sometimes necessary and for parents it will of course be necessary to ensure that any potentially harmful materials be moved.