A team of researchers led by economist Eugenio Proto from the University of Warwick in the UK wanted to know why Danes generally rank as the happiest people in the world. The 'happiness rankings' usually measure life-expectancy, living standartds, reported well-being and ecological footprint to assess which are the happiest countries on Earth.
In their study, published in the journal IZA as a discussion paper, they compared the genetic makeup of people in 131 countries to that of denizens of Denmark. And they have discovered that the greater the nation's genetic distance from Denmark, the lower their reported well-being, explains Kelly Dickerson from LiveScience.
The researchers also looked at scientific literature that suggests there is a link between mental well-being and variations of the gene SLC6A4, which helps transport serotonin, a chemical that makes you feel good. Then they looked at genetic data from 30 countries to see which populations had more variations of this gene.
“We looked at existing research which suggested that the long and short variants of this gene are correlated with different probabilities of clinical depression, although this link is still highly debated,” explains Proto in a press release. “The short version has been associated with higher scores on neuroticism and lower life satisfaction. Intriguingly, among the 30 nations included in the study, it is Denmark and the Netherlands that appear to have the lowest percentage of people with this short version.”
To further prove their theory, Proto and his team looked at well-being surveys from a group of Americans and traced their genetic origins. Those who reported to be the happiest descended from immigrants from the happiest countries, including Denmark, the Netherlands, and Sweden.
The paper is controversial, but the researchers hope their data can help us and other scientists better understand why some countries consistently report high levels of happiness.
Last year Denmark, Norway, Switzerland, the Neatherlands and Sweden were ranked the top five happiest countries on Earth—Australia got the 10th place.