Laughter and humor have been correlated to beneficial health outcomes, and research tells us the benefits of yoga are no less impactful. Both laughter and yoga have independently been shown to improve outcomes associated with heart disease. It is perhaps little surprise that preliminary results of a 3-armed study presented at the American Heart Association’s conference last weekend found laughter yoga to improve parameters of blood pressure and cortisol, compared to a control group.
The trial was three months in length, and three arms (or groups) were compared:
1) Laughter yoga: This group received laughter yoga classes, “a combination of breathing exercises and laughter stimulated through playful eye contact,” and watched Japanese comedy once every two weeks for one hour.
2) Music Therapy: This group was led in “listening to, singing, and stretching with music” in the same format as the laughter yoga group.
3) The control group received no intervention.
Both laughter yoga and music therapy groups showed significantly decreased cortisol levels (a measure corresponding with stress) following treatment sessions, and lower blood pressure immediately after the study; lower blood pressure persisted in both groups 3 months later, compared to the non-active control group.

The results are preliminary, as they have not yet been submitted to the rigorous process of peer review, and some experts question the findings due to the non-blinding of subjects. Still, the contributions raise interesting questions about the physiology of the role stress plays on blood pressure, as well as the unique contributions of yoga within this context. Says Eri Eguchi, lead researcher on the study, “We think yoga breathing may play some role for lowering blood pressure,” a link he’s planning to explore in future research.

Unclear from the press release is the specificity of the “laughter yoga” research protocol; that is, the proportion of time spent in each session devoted to watching Japanese comedy, and engaged in specific laughter yoga exercises. It sounds as if the laughter yoga element was primarily comprised of yogic breathing (pranayama) rather than yoga postures (asana); if so, this is the first study to document the positive role of yogic breathing on parameters of blood pressure and cortisol in synergy with laughter and humor.

Future studies should tease these elements apart and determine the differential contributions of laughter, humor, watching comedy, and yogic breathing on parameters of health.