I used to chew on ice constantly. I'd get a big glassful of it, and sit in front of the TV and crunch crunch crunch to my heart's content. I liked it best when it was dry and frosty.
And, um... I liked chalk. One of my siblings gave the whole family a set of sidewalk chalk as a Christmas toy-- this was when I was a teenager-- and it got stored in the bathroom for some reason, and one day I opened the drawer and there it was and it smelled... really good. So I started nibbling on it. You can't really eat chalk-- dries the mouth right out-- but over the course of a year I slowly chewed up and spit out all five colors. I just loved to munch it. So satisfying!
From the time I turned eighteen I've often offered to donate blood, but I'm usually rejected because my blood isn't dense enough; the red blood cell count is too low. They always tell me I'm anemic and recommend iron pills, but I tried that and decided the disease wasn't worth the cure. I don't have any symptoms from the anemia but I definitely get symptoms from the iron, so forget it. I'll just go my merry anemic way.
One day not long ago I read that one symptom of anemia is a strong craving for ice or chalk.
THAT explains it!