Why do some people compulsively crave and consume non-food items like soil or soap?

Health · Published 29 September 2026 Swipe more like this →

In short: Pica is a complex eating disorder defined by the persistent consumption of non-nutritive substances. While often dismissed as a childhood phase, it can signal serious health risks, including lead poisoning or intestinal blockage. Understanding its origins requires looking beyond simple cravings to the intersection of biology, psychology, and cultural practice.

Named after the Eurasian magpie—a bird known for its opportunistic feeding habits—pica involves the compulsive ingestion of items like plaster, plastic, or hair. To meet the clinical criteria established by the DSM-5, this behavior must persist for at least one month at a developmental stage where such actions are considered inappropriate. Crucially, the behavior must not be part of a culturally sanctioned practice, such as the traditional ingestion of kaolin clay, which is sometimes used to absorb plant toxins.

The health consequences of pica are significant and varied. Ingesting lead-based paint or contaminated soil can lead to severe poisoning, while consuming hair or other indigestible materials often results in surgical emergencies like intestinal obstructions or tearing. Furthermore, eating soil or feces carries the risk of parasitic infections, such as toxocariasis or leptospirosis. While pica is frequently associated with iron or zinc deficiencies, biological abnormalities are rarely the sole cause, and no single diagnostic test exists to confirm the condition.

Pica is most prevalent among pregnant women, young children, and individuals with developmental conditions like autism spectrum disorder. Recent research in Palestine among children with autism suggests that pica-related behaviors often correlate with sleep disturbances, highlighting the need for integrated screening in clinical services. Because patients often feel intense shame, they may hide their symptoms, leading providers to miss the diagnosis. Effective management requires a thorough assessment of nutritional status, including hemoglobin and mineral levels, alongside careful monitoring for potential toxic or infectious exposures.

The disorder remains a subject of active debate, particularly regarding its classification. Some experts argue it should be viewed through an obsessive-compulsive spectrum lens, while others emphasize sensory or psychosocial factors. Regardless of the underlying cause, the condition is only formally diagnosed when the behavior is severe enough to warrant medical attention beyond what is already provided for any pre-existing mental or physical health condition.

General information, not professional advice. Spotted an error? Flag the card or see corrections and complaints.

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