A pair of economists from the University of Warwick and Institute for the Study of Labor in Bonn compares happiness levels, as gauged by international surveys like the Gallup World Poll, World Value Survey and the European Quality of Life Surveys, in various countries and explores whether there could be a genetic component to being happy.
In their working paper, Eugenio Proto and Andrew Oswald note that factors like the country's wealth, social safety net services, and government quality all influence happiness, but that even when such factors are controlled for, Denmark is still the happiest place on Earth.
The duo further found that the smaller the genetic distance between another population and the Danes, the happier that other population was. For instance, LiveScience notes, countries close to Denmark like the Netherlands and Sweden also ranked high on the happiness scale while Ghana and Madagascar, which have low genetic similarity to Denmark ranked low on happiness.
Proto and Oswald also examined the happiness of Americans and found happy Americans had ancestors from happy countries. The duo also reported that a certain form of the serotonin gene is also linked to greater reported happiness.
"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," Proto says in a statement.
Psychologist David Meyers from Hope College tells LiveScience that a variety of factors influence whether someone is happy including sleep, exercise, and the relationships they have, though he notes that genes do seem to make a difference.
"Genes matter, much like the influence of genes on cholesterol levels," he adds. "And just as cholesterol levels are also influenced by diet and exercise, so happiness is also influenced by behaviors under our control."