The happiest place on EarthMads Claus Rasmussen / Reuters

The happiest places in the world are those where enlightened leaders shifted their focus from economic development to promoting quality of life.

“The biggest predictors of happiness are tolerance, equality, and healthy life expectancy,” Dan Buettner, a National Geographic writer and the author of The Blue Zones of Happiness, said Saturday at the Spotlight Health Festival, which is cohosted by The Aspen Institute and The Atlantic.

Buettner’s work found that Denmark, Costa Rica, and Singapore were the happiest places on Earth, in terms of how their citizens rated their own well-being. The U.S. was the 18th happiest. As Buettner wrote in National Geographic: “[A]bout three-quarters of human happiness is driven by six factors: strong economic growth, healthy life expectancy, quality social relationships, generosity, trust, and freedom to live the life that’s right for you.”

But, as Buettner noted, while the happiest places share many things in common, they each have unique factors that promote happiness. In Costa Rica, for instance, he said happiness can be attributed to the pleasure of living daily life; people smile, laugh, and interact with their friends and neighbors.

Denmark, meanwhile, exemplifies a society in which the state takes care of basic needs, such as education and health, leaving citizens to pursue their passions. Other Scandinavian countries do well in the World Happiness Index for the same reasons.

For its part, Singapore offers “life satisfaction.” Its citizens know that success lies at the end of a defined path: the right schools, the right job, and the right club.

Buettner said that promoting policies that make the happiest countries happy can help other nations make their citizens happier. “If you’re a leader interested in producing happiness, then promote” tolerance, equality, and healthy life expectancy, he said.

How to translate these lessons in happiness—or, to choose the term researchers involved in Buettner’s work studied, life satisfaction—to the individual? He said that by and large he can predict a person’s happiness by asking two questions: Is life short or long? Is life hard or easy? Those who said they found life to be long and easy were, on average, the happiest people, he said. Those who replied that it was short and hard were the least happy, he said. But there are steps that we can take to improve our life satisfaction, as Buettner told my colleague James Hamblin last year.

In terms of choosing a place to live, people who live near water—whether it’s a lake or river or an ocean—are about 10 percent more likely to be happy than people who don’t. And people who live in medium-sized cities are more likely to be happy than the anonymity of a big city or perhaps the too in-your-face, limited-possibility environment of a tiny town. You’re more likely to be happy if your house has a sidewalk, and if you live in a bikeable place.

Financial security is also, obviously, huge. It really does deliver more happiness over time than most anything that money can be spent on—after your needs are taken care of and you maybe treat yourself occasionally. If you have money left over, you’re much better paying down your mortgage or buying insurance or signing up for an automatic savings plan than you are buying a new gadget or new pair of shoes.

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