The human body has enough iron in it make a single nail: like one you pierce through wood with a hammer. People take iron salts and iron pills to prevent iron deficiency. Its not dangerous to eat iron, its only dangerous in high quantities. Some people take a type of liquid silver and ingest it, I don't remember the reason for the remedy, but it does exist. I believe sometimes if someone overdoses with silver their skin will turn blue.
Damn, this episode taught me something. Even when being mentally weak and pushing yourself down there's always something that keeps you going to do something not just for others but for yourself too. Which is how you can keep going no matter what negative thoughts or what other people say to you, it's how you push yourself up to be stronger as a human being.