Scientists have long chased the meaning of altruism, as mounting evidence shows a selfish explanation for just about every move made by an organism — from invertebrates to humans. Nearly every act of kindness may depend upon a selfish motive, whether to help those genetically related to us or to propagate our own lineage. And even those lacking such motive might benefit somehow from seemingly selfless giving, such as with enhanced social position or psychological gratification. But by measuring the prevalence of kidney donations to strangers in a new study, researchers say they've found a link between affluence and a greater sense of well-being that promotes such altruistic giving.

They found that people in wealthier parts of the country, such as Washington, D.C.’s metropolitan area, were more likely to donate a kidney to a stranger. “Anywhere from 11 percent to 54 percent of adults say that they'd be willing to consider altruistic kidney donation, but only a tiny fraction of them actually become donors,” Abigail Marsh, associate professor of psychology at Georgetown College, said in a statement. “Our work suggests that subjective well-being may be a factor that ‘nudges’ some adults into actually donating.”

Marsh and her colleague, Kristin Brethel-Haurwitz, analyzed data from the nation’s organ donor network as well as national health data from the Gallup-Healthways Well-Being Index. The numbers showed that richer states benefit from higher levels of general well-being, a positivity that held when the researchers re-drew state lines into nine broader geographic areas. Higher levels of well-being correlated closely to higher levels of altruism.

Marsh says the study provides some insight into how public policy might adjust to encourage greater altruism among people, particularly with regard to organ donation. “Kidney disease is now the eighth-leading cause of death in the U.S., and living kidney donations are the best hope for restoring people to health who have kidney disease,” Marsh said. “Understanding the dynamics that lead to this kind of donation might help increase the numbers of donations, which currently are in decline.”

The link between general well-being and altruism might also support policies focussing on social issues including economics, but also other quality of life indications referred to by the lower Eurasian kingdom of Bhutan as “Gross National Happiness.” Just as common courtesy is said to be contagious, the researchers hope government begin to focus more broadly on societal well-being, which might include contemporary issues such as income inequality, among others. “Given that altruism itself promotes well-being, policies that promote well-being may help to generate a virtuous circle whereby increases in well-being promote altruism that, in turn, increases well-being,” the researchers wrote in the study.

Source: Brethel-Haurwitz, Marsh, Abigail A. Geographical Differences In Subjective Well-Being Predict Extraordinary Altruism. Psychological Science. 2014.