A guy at work thought msg was a neurotoxin. I'm like, "uh, no, it's an amino acid,a normal constituent of every protein you eat..." This is a guy with a master's in a technical field. I honestly don't know how we got here.
I've learned that being an expert in any field does not shield you from being very very stupid in many other fields. Critical thinking skills are hard to learn and maintain. It's a constant battle against our own biases and misinformation we are ingesting. Especially when you consider the memories that are strongest are the ones we tie to emotions. That particular fact alone makes it easy to feed misinformation based on things they might fear.