Deborah Norville has written a new book, “Thank You Power: Making the Science of Gratitude Work for You”. She did research and interviews to find out whether being grateful actually heals. She found that a study at UC Davis showed statistically that grateful people are happier and healthier, they recover faster from trauma.
Maybe this study is similar to the one that shows religion and prayer makes people calmer and heal faster, too. Perhaps acceptance of the world around us and self acceptance helps us heal.
I think I've read studies about how gratitude has a measurably positive effect on one's health--cardiovascular, nervous system, etc. It makes a lot of sense to me--approaching life with gratitude and a "glass half full" rather than half empty attitude definitely does a lot to ease anxiety, stress, and depression. I find that focusing on the positives and thanking my stars for all the little and huge blessings in my life can be the fastest route toward getting out of a funk. I remember reading a self-help book that advised noting three things to be thankful for each time one wakes up and before one goes to sleep. It's still an activity I partake of to this day!