The COVID-19 pandemic has just started and I had a dry cough. I was pretty sure it was a nocebo effect, but even knowing it wasn’t helping, at some point it was so bad that I had to constantly mute myself on the streams. And you know when my cough stopped? After I got my first vaccine.
We need more research in this area; we cannot just discard it and say it is all in your head. Even knowing it is not real, it does have an effect on the body and can affect your real life.