At a young age, we are taught saying “please" and "thank you" is a sign of good manners. The verbal exchanges we have with our family, friends, and even strangers can impact the way we are perceived and can influence our old and new social relationships. According to a recent study published in the journal Emotion, saying “thank you” goes beyond being polite; it is the premise of social relationships, based on the find-remind-and-bind theory of gratitude.

The emotion of gratitude expresses appreciation for what one has, as opposed to what one wants or needs in a consumer setting. While most of us are extra grateful on the most thankful holiday of the year, Thanksgiving, science suggests we should go beyond that and actually exercise it in our daily lives. The simple but overlooked gesture can actually boost our well-being and happiness, in addition to our energy levels, optimism, and empathy, according to Psychology Today.

Social media websites, such as Facebook, Instagram, Blog, or Twitter, have fostered this idea with gratitude challenges (in their 7-, 10-, 21-, 100-, or 365-day forms), where a person posts verbal statements or photos of things they are grateful for on a daily basis. This becomes a public and ongoing gratitude journal. These gratitude challenges can have an effect on how strangers view the expressor, possibly signaling they are good candidates for a future social relationship.

To examine how these expressions of gratitude among strangers influence social relationships, and perhaps lead to new social bonds, researchers Sara Algoe from the University of North Carolina, and Monica Y. Bartlett, from Gonzaga University in Washington, recruited a total of 70 undergraduate participants to help pilot a new mentoring program supposedly run by the university. Based off Algoe’s find-remind-and bind theory of gratitude, which suggests gratitude starts new friendships (find), orients people to existing social relationships (remind), and promotes existing relationships (bind), the researchers believe people will be perceived as warmer when they give thanks and receive help, resources, or a favor. They created a situation in the lab where they could manipulate the expression of gratitude in a real way.

The participants in the pilot new mentoring program were required to act as mentors by giving advice on a writing sample from a high school student mentee. This writing sample was the one that the mentee planned to use for their university admissions. The scenario influenced the core points of gratitude.

A week later, the researchers divided the participants into two groups to test their gratitude theory. Half of the participants received a note from the mentee that simply acknowledged the advice (the control group), while the other half received a note that included an expression of gratitude from the mentee. The researchers asked the participants to complete a series of questionnaires to assess their impressions of the mentee and then were informed the study had concluded, The Conversation reported.

The researchers included a twist on the study. They casually mentioned the organizers of the pilot program had left a set of notecards for the mentors to complete if they wished to do so. The mentee would receive the note if they were accepted into the university. This was used as the dependent measure for actual social affiliation via gratitude.

The findings revealed all but three of the participants wrote a welcome note. The three participants who did not leave a note were in the control group. The researchers found 68 percent of participants left their contact details in their note when they received a thank you note from the mentee. However, only 42 percent who received the control note left contact details.

The mentees who expressed gratitude were seen as warmer people. This helps explain that saying “thank you” can help build and maintain social relationships via perceived warmth. The participants were more inclined to reciprocate gratitude when they saw the mentees were grateful as well.

The study highlights we need to be selective and choose to invest in social bonds that have the greater likelihood of being a “good investment.” If we are grateful, strangers may perceive us to be warm and empathetic, therefore, a potential person for a future social relationship. “While many questions remain for future research, our research provides initial evidence for the power of saying “thank you” to strangers,” said the researchers.

Saying “thank you” is not only a sign of gratitude but can also benefit our health, and overall well-being. The Greater Good Science Center at the University of California, Berkeley, suggests practicing gratitude consistently leads to stronger immune systems and lower blood pressure, higher levels of positive emotions, and feeling less lonely and isolated, among many others. Consider all the benefits of expressing gratitude next time you ask for directions, or need help at work.

Source: Bartlett MY, Williams LA. Warm Thanks: Gratitude Expression Facilitates Social Affiliation in New Relationships via Perceived Warmth. Emotion. 2014.