By Deborah Fields, BSc (Hons), PgDip, MCIPR
Pica is an eating disorder where an individual has a preference for eating items that have no perceived nutritional value to the human body. The disorder is most commonly exhibited by women and young children. Pregnant women can be especially prone to the disorder, which also affects people with learning difficulties such as autism.
The condition is mentioned in DSM-IV and is classified as a mental health condition, where it is described as eating of the specific items needs to continue for at least a month by a person who should be of an age at which he or she understands that the substance is unfit for eating.
Substances eaten by Pica Patients
Pica derives its name from the Latin word for ‘magpie’. The items eaten by affected people can widely vary from paper, chalk, clay, and detergents to plants, soil, hair, insects, and wood. The different eating preferences have been given specific names to describe them. For instance, xylophagia refers to a subtype of the condition in which affected individuals like eating wood, trichophagia describes preference to hair or wool, and geophagia refers to a preference for soil or clay.
Causes of Pica
Individuals who exhibit pica can fall into a number of different categories. The condition is very common in very young children who often grow out of the disorder as they develop an understanding of what kinds of foods are generally accepted.
Pregnancy can also trigger changes in women which makes them prone to craving items that they would not normally eat. There is also a link at times to low levels of minerals in a person’s body which attracts them to a particular item. For example, someone who is deficient in iron may seek out items with iron in their structure to compensate.
Psychiatric conditions such as obsessive compulsive disorder or schizophrenia can also make a person susceptible to eating items that are not nutritionally beneficial. At times, the preference can be the result of a cultural or religious practice. For example, some communities in the USA and Africa are known to eat clay.
How Common is Pica?
While it is difficult to arrive at an accurate number of affected people because people can be reluctant about admitting to eating substances that are not usually acceptable, around 8% to 65% of the population are thought to be affected by the condition at some point of their lives. This percentage may be at the higher side in certain populations that, for example, culturally value eating substances such as clay.
Symptoms and Health Risks
Eating items with no nutritional value can be dangerous. Eating soil and clay may lead to the person unintentionally picking up a parasite or exposing themselves to fecal matter or other impurities. There is also the risk that a sharp substance ruptures an internal organ on its way down the throat. The teeth can also be harmed from chewing hard substances that are not meant to be eaten.
How is Pica Treated?
If the person has a mineral deficiency, for example, health care professionals can provide treatment that can modify the diet to eliminate the deficiency. This approach has helped cure pica in some individuals.
Aversion therapy can help some patients realize which foods are good to eat and which are bad and unfit to consume. Medical professionals can provide training to help patients recognize the difference between substances suitable for consumption and substances that are not.
Therapies such as the ones involving the use of selective serotonin reuptake inhibitors are helpful in treating depression associated with Pica and are often taken in conjunction with cognitive behavioral therapy.
Reviewed by Susha Cheriyedath, MSc
Last Updated: May 22, 2016