ELI5 Iron - is body iron different to construction iron?

Is the Iron in our body different from the Iron used in construction? How did ancient cultures use meteoric iron without knowledge of metallurgy? What makes iron such a vital natural resource throughout human history? Why doesn’t iron in our blood react strongly to MRI machines? How does the imaginative concept of ""space swords"" link history and modern mythology around iron? ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: azhiker00, 18_usc_47, dependent_warning_51, lallo-the-long, boredcop, gnonthgol, gailynstarfire, 1strategist1. To the community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: [email protected]