It's no secret that gratitude is good for us, whether we're on the giving or receiving end. Multiple research studies have confirmed that practicing thankfulness increases our life satisfaction and leads to strong relationships. It's not hard to understand why being thanked provides a boost since we all like to feel appreciated. But why is it helpful to be thankful, and what gratitude practices lead to the most benefit?

A team of researchers from the University of Limerick set out to address some of these questions, and published their findings in the Journal of Clinical Psychology. They conducted a rigorous study that included a decent sample size (192 participants, 91 of whom completed the study) and a strong design. Participants were randomly assigned to one of three groups, all of whom wrote in journals three times per week for three weeks (and were sent text message reminders):

1. Reflective Gratitude: The first gratitude group was told to think back on their day and write about "the people you ... interacted with and are grateful for."  
2. Reflective+Expressive Gratitude: On top of the instructions given to the first gratitude group, this group was told to "express this gratitude to a person of your choice" through any means the participant wanted (e.g., face-to-face, email, social media). 
3. Active Control: The final group was told simply to write about the events of their day. They were considered an "active control" because they did what the other groups did, minus the gratitude component. Importantly, they were told the writing would be beneficial, and subsequently expected as much benefit from the exercise as did the other groups. Thus we can't attribute any differences in outcomes to different levels of expectancy.

The researchers were interested in the effects of these interventions on participants' gratitude (obviously), life satisfaction, positive vs. negative emotion (what they called "affect balance"), relationships satisfaction, and depression scores. Another strength of the study was its longitudinal design, with participants completing these measures  at baseline (before any of the writing exercises), after the three weeks of writing, as well as one month and three months later.
Several interesting results emerged. At the end of the intervention the Reflective+Expressive Gratitude group had the most positive changes in affect balance—more positive compared to negative emotion—as well as significantly reduced depression scores. These effects seemed to fade over time at the one and three month follow-ups, which is not surprising considering that most participants probably stopped doing the exercises.


Follow-up analyses revealed that expressing gratitude drove the improved emotional balance for the Reflective+Expressive group. In other words, we're likely to feel better the more we express our gratitude; just thinking and writing about our gratitude is less effective.
There was one additional wrinkle to this finding: Those who were more depressed got the most benefit out of expressing their gratitude. Thus when we're feeling down, it is probably all the more important that we notice and thank the people we're grateful for.

The study authors did not provide much discussion about why expressing gratitude may be so important. I would speculate that telling someone we appreciate them or something they did strengthens our relationships, and probably invites reciprocal shows of gratitude. As our relationships improve, we experience more positive emotions and better mood. The link between stronger interpersonal connections and well-being supports this explanation, though of course more work needs to be done to better understand these results.


In the meantime, there are plenty of reasons to notice the people in your life that you're grateful for, and to let them know. I invite you to try one of these today (drawn from the study's instructions):

• Thank someone face-to-face for something specific they did.
• Email a friend to express your gratitude.
• Write a thank-you message on Facebook or other social media.
• Hand write a personal note of gratitude and hand it to your friend or significant other.
• Send a short text message to someone in your life expressing your gratefulness.

For any that you try, notice the other person's reaction, and your own feelings. And as the study suggests, with ongoing gratitude practice we can continue to reap the benefits, both for ourselves and for our relationships.