Explanations for the Behavior

Although pica has been dismissed as pathological and aberrant for many centuries, evidence currently available suggests that pica may actually be adaptive. Experimental data indicate that the binding capacity of at least some pica substances makes them capable of shielding us from damage that would otherwise be inflicted by harmful chemicals and pathogens. The clay content may also have soothing anti-diarrheal or anti-nausea effects, similar to Kaopectate. (Indeed, Kaopectate takes its name from one species of clay, kaolin.) Furthermore, the demographic profile of those who engage in pica most frequently—pregnant women and young children living in the tropics—is also consistent with this hypothesis, since they are most biologically vulnerable.