Before this conversation degrades to outright name calling, which is what happens when facts become scarce (ad hominem attack, one of the logical fallacies), I offer this bit of info.

Might you be referring to heme iron?

Watch this... https://nutritionfacts.org/video/the-safety-of-heme-vs-non-heme-iron/

And this... http://www.synbiowatch.org/2017/08/bleeding-veggie-burger-has-no-basis-for-safety-according-to-fda/

Yes, I realize it’s a bleeding veggie burger. The point is the GMO additive.