[nomel]

Nocebo [1], a well know/documented phenomenon, can be very damaging.

[1] https://en.wikipedia.org/wiki/Nocebo

[card_zero]

On the other hand, the placebo effect works even when the placebo is clearly labelled "placebo". So I guess there's potential to tell people needlessly disconcerting facts and then take the edge off with reassuring bluster and functionless comforts.