system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why isn't iron in your blood affected by strong magnetic fields like an MRI?
gpt
Two reasons. The iron content is far too low (~1 mg of iron per liter of blood) for any observable effect. Iron in blood is not in a metallic state, but instead contained within hemoglobin, which has no net unpaired electrons.