Laughter therapy may improve specific domains of quality of life in cancer patients, according to preliminary research published in PLOS One.

“People in the city of Osaka, Japan like to laugh and make someone laugh. We wanted to prove the relationship between laughter and quality of life,” explained study author Toshitaka Morishima of the Osaka International Cancer Institute.

In the randomized controlled trial, 56 patients who had been diagnosed with cancer received four sessions of laughter therapy over the course of six or seven weeks.

The laughter therapy session “began with a laughter yoga routine (a group practice involving voluntary laughter, with a body exercise which includes stretching, clapping, and body movement),” the researchers explained in their study.

“This was followed by live performances of Rakugo (a form of Japanese verbal comedy performed by a lone storyteller sitting on stage) or Manzai (a traditional Japanese style of stand-up comedy involving jokes traded at high speed between two performers) by locally well-known professional entertainers.”

The therapy was associated with improvements in self-reported cognitive functioning and reductions in pain.

“With regard to the mechanism of cognitive function improvement, the positive emotions induced or accompanied by laughter may have enabled patients to reduce the stress response and ease tension by decreasing stress-making hormones such as cortisol, epinephrine, and growth hormone; this in turn can have a positive effect on the cognitive functioning of patients,” the researchers wrote.

“For the alleviation of pain, previous studies have reported that laughter therapy increases pain tolerance and reduces pain perception through physiological mechanisms for analgesia involving the release of endorphins.”

“When people are diagnosed with cancer, they should not forget to laugh,” Morishima told PsyPost.

However, he added that the findings need to be verified with future studies. More research is also necessary to examine whether laughter prolongs the survival time of cancer patients.

The study, “Effects of laughter therapy on quality of life in patients with cancer: An open-label, randomized controlled trial“, was authored by Toshitaka Morishima , Isao Miyashiro, Norimitsu Inoue, Mitsuko Kitasaka, Takashi Akazawa, Akemi Higeno, Atsushi Idota, Akira Sato, Tetsuya Ohira, Masato Sakon, and Nariaki Matsuura.