[1] says "Craving and chewing ice (pagophagia) is often associated with iron deficiency,", not what you claimed which is the opposite.
As far as I can see, there's no indication on this page as to how frequently iron deficiency leads to ice chewing.
As far as I can see, there's no indication on this page as to how frequently iron deficiency leads to ice chewing.
Huh? Are you saying that my source claims that chewing ice causes anemia?
So from that source you can't conclude that anemia "often" leads to chewing ice, it may very well be quite rare.
Abstractly, "A is often a consequence B" does not logically goes to "B often leads to A".
To use an extreme exemple, crossing paths with polar bears (chewing ice) is generally linked with dieing (anemia), but death is quite rarely caused by crossing paths with polar bears.
It also seems to miss the central point of my metaphor.