According to WebMD:
A placebo is anything that seems to be a "real" medical treatment -- but isn't. It could be a pill, a shot, or some other type of "fake" treatment. What all placebos have in common is that they do not contain an active substance meant to affect health.
It is a science based phenomena and I find it fascinating.
Before any drug is released to the public, it has to pass a placebo effect test.
The pharmaceutical company has to show with statistical significance, that their new drug can perform better than a placebo pill.
The reason is because humans have shown to recover from an ailment if they believed they were getting a drug.. irrespective of whether they are.
There was a big debate some years ago about the efficacy of antidepressants when compared to placebo. Particularly considering the lack of side effects in a placebo.
What does this mean?
1) Most people are able to get positive benefits from their mind alone.
Think Wim Hof
2) People have increased confidence that a pill/remedy from a doctor, will likely work on curing them.
I am particularly fascinated by (1).
How limitless can I get with my mind?