This article states that some shelled animals - spiders, scorpions, crabs, worms and other creatures - have metal atoms in their claws, jaws and fangs. I believe through anabolism, since they eat sand, soil and insects that are full of a mix of those.
For most human beings, it would seem silly to eat soil or sand, or even insects - and yet, I wonder if our bodies would be able to digest and create anabolic processes around, for example, metals, in such way that we would end up having stronger bones / teeth / hair / nails (or other things).
To a certain extent, I also wonder how anabolism isn't use to regenerate cells that become old or faulty in the body as we age or get sick (a special diet would help "regenerate" blood balance, feeble skin, brain cells, etc, if we knew what foods would turn into these cells the best by anabolic process).
This question is becoming a bit confused, so I'll end up rephrasing it: is there a document / research / map / experiences of all the foods & materials that the human body can not only digest (and in what quantities) but also how they transform into our cells (and a list of foods / materials that are NOT taken into account by anabolic processes). I.e., at what speeds they can become part of us, and how they can/could change and alter the body cells in a strengthening kind of way (not in a way that makes us sick or dead).
NOTE: I am not a scientist, just a writer, but I am fondly interested in the subject.