Emmons worked with three experimental groups over the course of ten weeks. Those in the first group were asked to list five things they were grateful for that had happened in the last week. This was called the "gratitude condition." The second group was asked to list five daily hassles from the previous week. This was called the "hassles condition." Members of the third group simply listed five events that had occurred in the last week, but they were not told to focus on the positive or negative aspects. This was the "events or control condition."
Some of the things that people in the gratitude condition listed included "waking up in the morning," "the generosity of friends," and "thanks to God for giving me determination." Examples of hassles that were listed included "hard- to-find parking," "messy kitchen no one will clean," "finances depleting quickly," and "doing a favor for friend who didn't appreciate it." The last group listed such things as "talked to a doctor about medical school," "learned CPR," "cleaned out my shoe closet," and "attended Whole Earth Festival."
The gratitude group came out way ahead. They felt better about their lives as a whole, were more optimistic regarding their expectations for the upcoming week, spent significantly more time exercising (nearly 1.5 hours more per week), and reported fewer physical complaints.
Other studies have shown benefits from gratitude. Participants who kept gratitude lists were more likely to make progress toward important personal goals (academic, interpersonal, and health-based) over a two- month period compared to subjects in the other experimental conditions. Those in the gratitude condition were also more likely to report having helped someone with a personal problem or having offered emotional support to another.
Saying thank you is not just good manners. The process of recording your gratitude on paper and even delivering it yourself to the person to whom you're grateful can go a long way in boosting your happiness. One study asked some of the participants to write and then deliver in person a letter of gratitude to someone who had been especially kind but had never been properly thanked.4 After doing this for one week, researchers found that participants were happier and less depressed. This result was seen as far out as one month from the date of the gratitude visit. What the researchers are now trying to figure out is whether repeating this on a monthly basis is the best way to achieve happiness for longer periods of time.
Why does showing gratitude work? Noted experts such as Martin Seligman believe that it amplifies good memories about the past and creates strong bonds with someone from your past who is important. Thanking others for good deeds has become so customary that it is more of a reflex than a heartfelt display of appreciation for an act of generosity. By taking the time to really think about why you're grateful, to write a letter of thanks, and to deliver that letter in person, you can feel the real power of appreciation that makes you feel good about acknowledging someone for his or her good deeds.