An endless supply of more stuff may seem appealing when we’re young, but the conventional wisdom holds that happiness in adulthood breaks free from material possession. Adults prefer love, compassion, meaningful experiences. Now a Harvard University study adds some scientific reinforcement to that idea, as a team found spending money on others increased happiness scores far more than did personal indulging.

Researchers have been studying happiness for decades, painting the state of mind as a complex relationship between experience and memory — most notably popularized by the behavioral economists Daniel Kahneman and Amos Tversky. While personal fulfillment, in the form of self-reward, can make us temporarily content, experts suggest that increasing others’ happiness works to satisfy our own need to be social. Through helping others grow happy, beginning as early as infancy, we help ourselves grow happy, too.

Spend, Spend, Spend

The new Harvard study builds upon a laundry list of prior studies that seek to examine happiness’ relationship to outward spending. Psychologists Elizabeth Dunn, Lara Aknin, and Michael Norton sought to deepen this understanding by rounding out previously American studies, among people of a certain age, to a larger international scope with less restriction on participants’ age. Prior research has remained mostly limited.

Consider a 2008 study where people had to spend a windfall of either $5 or $20 on themselves or on others, depending on the prescribed condition. “That evening, people who had been assigned to spend the money on someone else reported happier moods over the course of the day than did those people assigned to spend the money on themselves,” they wrote in their latest report. Though limited in scope, the study illuminated a startling dilemma about human behavior: Do people spend money incorrectly, thinking personal reward will make them happier?

Initially, that answer seemed to be a resounding “yes,” as upon questioning, people predicted the opposite would be true. By and large, they believed having more money and spending it all on yourself would make people happier. As it turned out, spending money on others — regardless of the amount — led to increased happiness.

Happily, this phenomenon seems to transcend biological maturity. A 2012 study suggests there may be something more innate to us humans that simply finds joy in putting a smile on someone else’s face — an effect often referred to as the “warm glow.” Aknin and her colleagues found that children under the age of 2 were still visibly happier when they offered a puppet some of their goldfish crackers than when they received some themselves. What’s more, the relationship holds in over 100 countries.

With all this in mind, a more relevant question emerges: When does prosocial spending — that is, in the financial interests of others, at a personal cost to you — pay the greatest dividends for the spender?

Self-Interest Without Selfishness

Aknin and her team find three criteria satisfy giving as being self-serving, as prior research indeed shows that not all forms bring the giver happiness. These criteria include: relatedness, competency, and autonomy, and together they make up a notion in social psychology known as “self-determination theory.” Spending money on others, with the goal of being self-serving yet unselfish, may accomplish all three.

Relatedness reflects a person’s ability to connect with someone in their act of giving. Competency implies the person’s actions can reliably make a positive difference. And autonomy means the person is giving of their own free will, not because he or she was coerced into doing so.

Basically, the theory holds that people enjoy helping others — more people would donate to charity, the researchers argue, if charities could better fulfill the three criteria. Unfortunately, the inability to connect to the person (or animal) benefitting from the donation, coupled with the distrust the donation will even reach its intended target, means many people decided not to give. They aren’t cold-hearted necessarily, and the charity isn’t a poor marketing agent; the basic triggers of human psychology simply aren’t being met.

More broadly, the team explains, the study’s robust knowledge base could be applied to other society-wide causes, such as the failures of socialized health care in the U.S. or the chemical forces that compel one person to gain more happiness than another when he or she gives, by way of the “bonding hormone,” oxytocin.

“The benefits of prosocial spending are evident in givers old and young in countries around the world,” the team concludes, “and extend not only to subjective well-being but objective health” as well.

Source: Dunn E, Aknin L, Michael N. Prosocial Spending and Happiness: Using Money to Benefit Others Pays Off. Current Directions in Psychological Science. 2014.