Why laugh?

Most of us don't know the benefits of laughing. Research shows it can exercise muscles, nerves and organs in your torso. It causes the heart to beat faster and blood pressure to rise, then drop to a point that's lower than where it started. Feelgood endorphin hormones are released, and experiments at the Lorna Linda University School of Medicine in California have shown that laughing helps the immune system to create white T-cells that help fight infection.

Daily Express newspaper (Tuesday, 15 February 2005)