There are some preconceptions about placebos and the placebo effect. You might be surprised to read, for example, that ‘placebo pills’ are not needed to achieve a ‘placebo effect’. This article unpacks six perhaps surprising features of the placebo effect, namely:

1. Placebos have a dark cousin: nocebos
2. Placebos work even if people know they are placebos
3. Honest placebos are ethically acceptable
4. Placebo effects are part of most treatment effects
5. You don’t need placebos to have placebo effects
6. You can generate placebo (and nocebo) effects in yourself