Pica is the medical term for unusual cravings, particularly for substances that are considered indigestible (not food stuffs). Apart from cravings, persons with pica may actually consume indigestible materials, like paint chips, sand, chalk, dust, cigarettes ash, burnt match sticks, soap or paper. Pica is a symptom associated with nutritional deficiencies but may also be noticed in persons with mental disabilities (retardation).
Children who eat sand and other unusual substances may not be doing so due to pica but rather this may be a way of exploring their surroundings with their different senses. Children may also consume their nose pickings (‘boogers’) and ear wax and in some cases, even their feces or animal droppings.
Pica is a symptom associated with severe iron-deficiency anemia (low blood iron) and may also sometimes be present in pregnancy.