Do happy people live longer?...http://science.howstuffworks.com/life/happy-people-live-longer.htm/printable
Even short-term gaiety may boost your body's defenses. In a Tufts University study, researchers separated subjects into two groups of people: one group watched comedic films while the other suffered through stressful ones. The group who spent their time laughing saw their circulation improve as though they'd been exercising while the other group experienced reduced flow. In addition, when subjected to stressful events afterwards -- sending stress hormones skyrocketing -- the people who spent their time laughing recovered much more quickly, their heart rates fast returning to normal [source
I'm so mean and grumpy I'll outlive both cockroaches and Twinkies.
The way I see it, people who are perpetually happy-go-lucky and laughing at everything don't really have the necessary skills to cope with disasters. It's a quantum leap from happy to tragedy, whereas from tragedy to happy is just a walk in the park.
Being optimistic is SO energy-draining!

I'm not sure that laughter is a panacea but I do think that people who can find solace in their grief, strength in adversity and joy in small things live more satisfying lives than people who are self centred and driven to achieve worldly success. The former certainly smile more.

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