The practice of laughter yoga began in 1995, when it was invented by Madan Kataria, a doctor, in Mumbai, India. Today its practitioners attend one of thousands of classes offered all over the world. They say they gain health benefits, including stress reduction and an improved immune system.

Kurt Andersen and Mary Harris, host of WNYC’shealth podcast Only Human, were curious so they decided to attend a class in New York recently. It was through an organization called Yogalaff, and it was held in a chiropractor’s office in the basement of an office building.

It wasn’t what they had expected at all.

For starters, Kurt and Mary learned, laughter yoga is not like conventional yoga. There are no mats, and no one does downward dog poses or headstands. It’s more like improv comedy exercises, where everyone pretends to do something silly like speak gibberish or roar like a lion. As for the laughter — it’s more like making the sound of laughter. That fake laughter, ideally, turns into real laughter.

“I first want to say that there’s no wrong way to laugh,” said Jonathan Applefield, who was leading the laughter yoga class that night. “So if you don’t feel like laughing, it you fake it, we fake it till we make it.”

A guiding principle of laughter yoga is that the body doesn’t differentiate between real and forced laughter, and the health benefits achieved are identical.

Mary takes a step back to find out the history of laughter yoga, tracing it to the magazine editor Norman Cousins. His memoir of recovering from illness by using laughter, “Anatomy of an Illness,” became a bestseller in the 1970s and launched the idea of laughing as therapy. That inspired Kataria to start laughter yoga, decades later.

Kurt and Mary’s adventures in laughter yoga continue in part two.

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