At the same time, I would not restrict what a grown rational and self-aware human (emphasize rational and self-aware) is and isn't allowed to do with themselves

At the same time, I would not restrict what a grown rational and self-aware human (emphasize rational and self-aware) is and isn't allowed to do with themselves. See biohackers, attempts at cyborg conversion, and Dallas Buyers Club. I don't recommend it. But whatever, they are individual agents. Of course, if they're actively promoting misinformation, especially that which affects people negatively, as Ron Woodroof apparently did with AIDS drugs, that's another story....