laughter is the best medicine

study links sense of humor to survival:

Adults who have a sense of humor outlive those who don't find life funny,
and the survival edge is particularly large for people with cancer,
says Sven Svebak of the medical school at Norwegian University of Science and Technology

The greater a role humor played in their lives,
the greater their chances of surviving the seven years, Svebak says.
Adults who scored in the top one-quarter for humor appreciation
were 35% more likely to be alive than those in the bottom quarter, he says.

In a subgroup of 2,015 who had a cancer diagnosis at the start,
a great sense of humor cut someone's chances of death by about 70%
compared with adults with a poor sense of humor, Svebak says.