When do I feel good when I am nice? A diary study about the relationship between prosocial behavior and well-being

Previous research has shown that prosocial behavior not only benefits the person being helped, but also promotes the well-being of the person helping. Still, several specific characteristics of the helping situation have not yet been considered in one single study. Thus, we examined under which circumstances the helper's well-being is more or less positively influenced. We carried out a 7-day diary study with 363 participants who reported on their everyday prosocial behavior as well as their well-being. We examined the effect of 13 potential moderation variables based on theoretical assumptions of self-determination theory and theories about reciprocity and altruism, as well as invested resources. Overall, the results replicated the positive effect of prosocial behavior on well-being. However, the helper's autonomy, the recipient's gratitude and low responsibility for the situation, the improvement of the situation through helping, and low expected self-blame (when not helping) on the side of the helper were necessary conditions. Moreover, taking within-subject effects into consideration, significant random effects in multilevel models showed that the effect of prosocial behavior on well-being can highly differ from person to person, emphasizing that not all people under all circumstances are happier when they help others.