More evidence that smiling/laughing promotes long life:

"Facial expressions are a barometer of the emotions , and like emotions, they vary in form and intensity. “Duchenne smilers”, who engage muscles both near the corners of the mouth and around the eyes, are known as genuine smilers. Ernest L. Abel , from Wayne State University (Michigan, USA), and colleagues, link smile intensity to longevity".


[link to www.worldhealth.net]