Study reveals laughter really is the best medicine

People feel less pain after a good laugh, because it may cause the body to release chemicals that act as a natural painkiller, research has suggested.
The researchers at the University of Oxford also think the ability to belly laugh was unique to early humans. This, they believe, enabled our ancestors to form much larger tribal groupings than the ape-like species that lived alongside them.
The research is published in the Proceedings of the Royal Society B. The experimenters first tested the pain thresholds of volunteers. They were then split into two groups, with one being shown 15 minutes of comedy videos, while the other was shown material the researchers deemed boring - such as golfing programmes.
The researchers found that those subjects that had recently experienced belly laughs were able to withstand up to 10% more pain than they had done before watching the videos. To their surprise, the scientists also found that the other group was less able to bear pain after watching 15 minutes of the "boring" programmes.

Source  - BBC