Geographical differences in subjective well-being predict extraordinary altruism.

Altruistic kidney donation is a form of extraordinary altruism, the antecedents of which are poorly understood. Although well-being is known to increase the incidence of prosocial behaviors and there is significant geographical variation in both well-being and altruistic kidney donation in the United States, it is unknown whether geographical variation in well-being predicts the prevalence of this form of extraordinary altruism. We calculated per capita rates of altruistic kidney donation across the United States and found that an index of subjective well-being predicted altruistic donation, even after we controlled for relevant sociodemographic variables. This relationship persisted at the state level and at the larger geographic regional level. Consistent with hypotheses about the relationship between objective and subjective well-being, results showed that subjective well-being mediated the relationship between increases in objective well-being metrics, such as income, and altruism. These results suggest that extraordinary altruism may be promoted by societal factors that increase subjective well-being.