New Orleans, LA - Laughter is the best medicine, a cliché to be sure, but a new study has shown that laughter yoga, a blend of playful laughter exercises coupled with gentle breathing and stretching, can significantly lower systolic and diastolic blood-pressure levels, as well as bring about significant reductions in the stress hormone cortisol [1].

Dr Madan Kataria

"Laughter yoga is a concept where anybody can laugh for no reason at all," Dr Madan Kataria, lead investigator of the study and founder of the Laughter Yoga school. "You don't need any jokes, any humor, or any comedy. You don't even need to be happy. What we do is laugh in a group and initiate laughter as a form of bodily exercise, but when we have eye contact with others, this laughter becomes real and contagious."

This laughter, explained Kataria, when combined with yoga breathing to bring more oxygen to the body and brain, results in significant biological and physiological changes, such as the reductions in blood-pressure and stress levels.

Speaking with heartwire here at the American Society of Hypertension 2008 Annual Meeting, Kataria said the idea of laughter yoga began in 1995 with just five participants in Mumbai, India. Now there are more than 6000 laughter clubs in 60 countries, and the present study was designed to show that real health benefits could be obtained from this simple form of exercise.

The investigators studied 200 male and female individuals within the information-technology industry in India, a group that is particularly stressed due to the demands of their job, said Kataria. These individuals participated in a typical laughter yoga session, which lasts about 20 to 30 minutes. Subjects simulate laughter for 45 seconds to one minute, beyond the typical burst of laughter, which is followed by deep breathing and gentle stretching. This process is repeated for the duration of the session.

The 200 subjects completed seven sessions of laughter yoga over a three-week period. At the end of the "treatment," subjects who laughed reduced their systolic blood pressure more than 6 mm Hg, a significant change from baseline and also significant when compared with a nonlaughing control group. Diastolic blood pressure was also significantly reduced. Cortisol levels, a hormone released during periods of stress, were reduced in the laughter group, and perceived stress levels, as measured by standardized questionnaires, were improved.

Changes in blood pressure from baseline after three weeks of laughter yoga

Measurement	Laughter yoga group (n=200)	Control group (n=100)
Pretreatment systolic blood pressure (mm Hg)	128.24	125.89
Posttreatment systolic blood pressure (mm Hg)	120.78a	125.96b
Change (%)	-6.18	0.06
Pretreatment diastolic blood pressure (mm Hg)	82.37	82.34
Posttreatment diastolic blood pressure (mm Hg)	79.34a	81.8 b
Change (%)	-3.82	-0.65

"To bring about physiological and biochemical changes, laughter has to be hearty, from the belly," said Kataria, a medical doctor who once worked in Mumbai. "Second, laughter must be extended. Laughter in real life lasts for a couple of seconds and then is done, but this isn't enough. That's why laughter in laughter yoga is hearty laughter extended for a period of time until our physiology changes. Also, it is unconditional. You're not dependent upon any conditions except the ones that we create."

Kataria told heartwire that resistance to the treatment is strongest in Asian cultures but said many in the US have embraced the practice. He said the process allows people to "act happy" in order for this feigned laughter to become genuine and real, something that is good for the mind and the body.

A second, smaller study also presented at the meeting involved assessing the benefits of daily sessions of music. Investigators, led by Dr Antonella Ferrari (University of Florence, Italy), showed that listening to 30 minutes of rhythmically homogenous music for one month—classical, Celtic, or Indian—combined with slow, abdominal breathing exercises significantly reduced systolic blood pressure as measured by 24-hour ambulatory blood pressure in 48 hypertensive subjects.

Asked to comment about these findings with unconventional methods, Dr Sandra Taler (Mayo Clinic College of Medicine, Rochester, MN) told heartwire that both studies involved breathing exercises, which appears to be key in reducing blood-pressure levels. Dr Gerald Berenson (Tulane Center for Cardiovascular Health, New Orleans, LA) agreed, saying there is a lot of evidence linking respiratory function and blood pressure and heart rate. "Relaxation techniques have been of interest for a long time to control things like blood pressure."

"I think the key with all of these methods is whether the patient will continue," added Taler. "On the plus side, they might be very willing to try something non-drug-related, possibly added to their medications, rather than adding another medicine."

Dr Kataria is the founder of Laughter Yoga and travels extensively to provide information, training, retreats, and corporate seminars. Laughter clubs are mostly free and public.