[goku12]

Apparently, oxygenated hemoglobin and blood plasma are diamagnetic, while deoxygenated hemoglobin is paramagnetic. Meaning, magnetic properties are determined by the molecules, not its elements. I assume that whatever attraction or repulsion caused by even the MRI magnets are weak compared to the forces involved in Brownian motion. So don't expect anything substantial.

[SwiftyBug]

This reminds me of something I've always thought that Toph – spoiler about Avatar: The Last Airbender – should also be able to blood bend since she created metal bending and the blood is full of iron.

[goku12]

There is a scene in one of the X-men movies where Magneto escapes a completely non-metallic prison by extracting iron from a guard's body. I initially thought that Raven had injected him the previous day with something to increase his iron content. But realized later that she had injected metallic iron as a suspension.

That aside, you don't need ferromagnetic substances for it be manipulated by magnetic fields. Anything conducting can be moved around by fluctuating magnetic fields. Even non-conducting paramagnetic or diamagnetic substance will eventually respond to very high strength magnetic fields - just not at the 'feeble' strengths of an MRI machine's superconducting magnets. Here is something I collected previously on the same fun topic: https://phanpy.social/#/fosstodon.org/s/111504060685437481?v...

[msgodel]

That's not so surprising. Iron isn't magnetic in all its oxidation states.

[goku12]

Why were you downvoted? I was going to read more on it later. So far, I know that Iron III oxide is magnetic. I don't know anything about the other oxides, ions in other oxidation states or iron in other compounds. I wish the people explained the reason why they downvoted.