Positive emotions are highly valued and frequently sought. Beyond just being pleasant, however, positive emotions may also lead to long-term benefits in important domains, including work, physical health, and interpersonal relationships. Research thus far has focused on the broader functions of positive emotions. According to the broaden-and-build theory, positive emotions expand people’s thought–action repertoires and allow them to build psychological, intellectual, and social resources. New evidence suggests that positive emotions—particularly gratitude—may also play a role in motivating individuals to engage in positive behaviors leading to self-improvement. We propose and offer supportive evidence that expressing gratitude leads people to muster effort to improve themselves via increases in connectedness, elevation, humility, and specific negative states including indebtedness.

Objective

Prosocial behavior has been linked to improved physical health, but the biological mechanisms involved remain unclear. This study tested whether a 4-week kindness intervention could reduce expression of a stress-related immune response gene signature known as the Conserved Transcriptional Response to Adversity (CTRA).

Methods

In a diverse sample of community adults (N = 182), study participants were randomly assigned to perform 3 kind acts for other people, to perform 3 kind acts for themselves, or to list daily activities (control), on one day per week over 4 weeks. CTRA gene expression was measured by RNA sequencing of dried blood spots (DBS) collected at baseline and 5 weeks later (1 week after completing study assignments). Participants' descriptions of their kind acts were coded for protocol adherence and act content.

Results

Participants who were randomized to perform kind acts for others showed significant reductions in CTRA gene expression relative to controls. Participants who were randomized to perform kind acts for themselves also showed significant reductions in CTRA gene expression relative to controls, but this pattern emerged only for those who failed to perform the requested self-kind acts (protocol non-adherent). Those who fully adhered to the self-kindness protocol showed no change in CTRA gene expression and did not differ from controls. Act content analyses implicated self-stress-reducing behavior in the paradoxical effects of self-kindness and the physical presence of others in the effects of prosocial behavior.

Conclusions

Prosocial engagement-doing something kind for others rather than oneself-reduces CTRA gene expression. The nature of kind acts and their intended recipient plays a key role in shaping the genomic impact of kindness.

Context

Prosocial behavior is linked to longevity, but few studies have experimentally manipulated prosocial behavior to identify the causal mechanisms underlying this association. One possible mediating pathway involves changes in gene expression that may subsequently influence disease development or resistance.

Design, setting, participants

In the current study, we examined changes in a leukocyte gene expression profile known as the Conserved Transcriptional Response to Adversity (CTRA) in 159 adults who were randomly assigned for 4 weeks to engage in prosocial behavior directed towards specific others, prosocial behavior directed towards the world in general, self-focused kindness, or a neutral control task.

Results

Those randomized to prosocial behavior towards specific others demonstrated improvements (i.e., reductions) in leukocyte expression of CTRA indicator genes. No significant changes in CTRA gene expression were observed in the other 3 conditions.

Conclusion

These findings suggest that prosocial behavior can causally impact leukocyte gene expression profiles in ways that might potentially help explain the previously observed health advantages associated with social ties.

Online interventions that elicit kindness may enhance well-being. We tested the efficacy of three kindness interventions among breast cancer survivors. Participants (N = 137, M age = 62.65 years) were randomized to perform acts of kindness for others, acts of kindness for self, self-kindness meditation, or a daily-activities-writing control and completed three activities each week for 4 weeks. Primary (well-being, depressive symptoms) and secondary outcomes (social support, self-kindness) were assessed pre- and post-intervention. No differences emerged in the primary outcomes. However, relative to controls, participants in the acts of kindness to others condition reported greater increases in social support, and participants in the self-kindness meditation condition reported greater decreases in self-kindness. Among breast cancer survivors, performing prosocial acts may enhance feelings of social support. The two self-kindness conditions yielded either null or detrimental effects, suggesting that further research is needed on best practices for conducting self-focused kindness interventions.

Although gratitude is typically conceptualized as a positive emotion, it may also induce socially oriented negative feelings, such as indebtedness and guilt. Given its mixed emotional experience, we argue that gratitude motivates people to improve themselves in important life domains. Two single-timepoint studies tested the immediate emotional and motivational effects of expressing gratitude. We recruited employees (n = 224) from French companies in Study 1 and students (n = 1026) from U.S. high schools in Study 2. Participants in both studies were randomly assigned to either write gratitude letters to benefactors or outline their weekly activities (control condition). Expressing gratitude led to mixed emotional experiences (e.g., greater elevation and indebtedness) for employees and students as compared with the control group. Students also felt more motivated and capable of improving themselves, as well as conveyed stronger intentions to muster effort towards self-improvement endeavors.

Gratitude has been associated with better physical health. Yet, surprisingly little research has experimentally investigated the capacity of gratitude to motivate individuals to eat more healthfully. In Study 1, among undergraduate students (N = 327) attempting to achieve a healthy eating goal, state gratitude following a writing activity significantly predicted healthier eating behavior 1 week later. In Study 2, across a 4-week intervention, 9th and 10th grade students (N = 1017) from four high schools were randomly assigned to either write weekly gratitude letters or to list their daily activities each week (control). Teens who expressed gratitude reported healthier eating behavior over time, relative to controls, and this effect was partially mediated by reductions in average negative affect across the intervention period. Thus, our findings suggest that gratitude-based interventions may facilitate improvements in healthy eating behavior in adolescents and young adults.

Could 10 min of gratitude per week have the potential to change the trajectories of young students' lives? With over 1,000 ninth- and tenth-grade students, we tested whether a simple 4-week classroom-based gratitude intervention would prompt increases in well-being and motivate students to become better people and attain better grades. Over the course of 1 month, students were assigned to spend 10 min each week writing gratitude letters to their parents, teachers, coaches, or friends and completing additional gratitude-related reflection activities or to try to become more organized each week by listing their daily activities and reflecting on the obstacles and benefits (control). Importantly, relative to controls, students in the gratitude conditions reported greater LS and motivation to improve themselves and maintained these levels throughout the semester. This sustained self-improvement motivation and LS were partially mediated by increases in feelings of connectedness, elevation, and indebtedness. Interestingly, negative affect partially mediated the effect of gratitude on LS, but not on improvement motivation. No group differences emerged in academic performance over time. This study provides evidence that expressing gratitude and reflecting on their benefactors' actions may help keep high school students motivated and satisfied with their lives over the course of a semester. (PsycInfo Database Record (c) 2022 APA, all rights reserved).