Studies have shown that feeling and expressing gratitude actually improves health and happiness. According to researchers at the Greater Good Science Center at the University of California-Berkeley, a grateful attitude may help boost immunity and lower blood pressure, decrease feelings of loneliness, foster generosity and compassion and generally improve emotional well-being.

And an article in Harvard University’s HEALTHBEAT journal suggests writing thank-you notes is a way to ingrain that grateful attitude into everyday life.

So they need to be hand written? We can't just send texts and Facebook comments?

Texts, emails and FB thanks are fine for peers  but you should follow-up with handwritten notes to express gratitude of, er, note.

"Newman says that despite the general trend toward digital communication, people should take time to put pen to paper. 'I feel like the cost of doing that in terms of time and resources is very small,' she says."

Easy for her to say. Between looking up snail mail addresses and figuring out what to write...

Jimmy Fallon knows the value of writing Thank You notes.

http://www.hitfix.com/comedy/12-funniest-thank-you-notes-from-late-night-with-jimmy-fallon

Ha!