A highly cited study by UCLA and the University of Miami found that people who wrote down what they were grateful for on a weekly basis were more cheerful and optimistic about the upcoming week than those who didn't. They also had fewer doctors visits and missed fewer days of work.
A separate study published in The Journal of Psychology supports these conclusions. Keeping a daily journal of moments or events of things you're grateful for is linked to increased happiness, researchers conclude.
And happiness plays an important role in our careers.
Positive people are more likely to perform better on assigned tasks and are more likely to get favorable evaluations by supervisors, research shows.
Billionaire and media mogul Oprah Winfrey has long been an advocate of keeping a journal for tracking gratitude.
"You radiate and generate more goodness for yourself when you're aware of all you have and not focusing on your have-nots," Winfrey writes on her website.
"Shark Tank" judge and multi-millionaire Daymond John is another successful businessperson who publicly discusses the importance of gratitude.