SEATTLE -- Know the saying 'laughter is the best medicine'? Turns out it's true.

Take it from an expert. Chip Lutz is the laughter leader trainer with the World Laughter Tour, an organization that strives to lead the world to health, happiness and peace through laughter.

"It's an impossibility for the negative and positive emotions to occupy the space and same time in your head. So when you start laughing those bad thoughts are gone," said Lutz.

Researchers have found laughing changes your body's chemistry, relieving pain.

"It can help improve our immune globulin," said Dr. Carrie Horwitch of Virgina Mason Medical Center.

Marylou Richardson says she's walking proof that the power of laughter can help beat the hardest of times.

"After my husband died I couldn't sleep. For seven months I just wasn't sleeping at all, but after the first session I slept for 12 hours," she said.

Lutz is leading a class at Virginia Mason for people who want to become certified laughter leaders. The idea is that Lutz's students would then go on to encourage others in their lives to let out at least a few chuckles.

Lutz says a good belly laugh could cure the whole body by bolstering the immune system.

More Information:

World Laughter Tour