Eating non-food sources is a disease or condition referred to as PICA.  As
far back as ancient Greece, we have documentation of this disorder.  It is
common to find children and pregnant women ingesting non-food sources
(dirt, laundry starch, paint chips), but it is not desireable.  There had
been an OLD theory that people with trace mineral deficiencies did this to
obtain something that was missing in their diet.  It has been disproven
that this actually works in that direction.  What seems to be happening is
that people with some other imbalance eat non-food items, such as dirt, and
the trace minerals in these substances actually CAUSE the deficiency.  The
most common case is with iron-deficiency anemia...children ingesting
lead-based paint chips will have low iron levels because the lead is
actually binding to the site that iron should be binding.  Make sense to
everyone?  There's lots of folk-wisdom out there on this topic, but recent
studies (and yes, I CAN dig up, so to speak, the citations if you need
them) do not show the direction of causality, that is the temporal
relationship, that we once thought existed.
Chris

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: )Chris Hafner-Eaton, PhD, MPH, CHES, IBCLC  email: [log in to unmask]  : )
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