Happier countries, longer lives: an ecological study on the relationship between subjective sense of well-being and life expectancy.

The relationship between sense of well-being and longevity is not well-established across populations of varying levels of socioeconomic status. We sought to examine the relationship between happiness, or subjective sense of well-being and life expectancy using data from 151 countries. This analysis is based on the 2012 Happy Planet Index project conducted by the Center of Well-Being of the New Economics Foundation, based in the United Kingdom. Well-being data for each country were taken from responses to the 'Ladder of Life' question in the 2012 Gallup World Poll in which participants were asked to rate their quality of life on a scale from 1 (worst possible life) to 10 (best possible life). Life expectancy and gross domestic product data were taken from the 2011 United Nations records. Ecological footprint data were taken from Global Footprint Network records. Subjective sense of well-being was highly correlated with life expectancy (Pearson correlation r = 0.71, p < 0.0001). In a multivariable linear regression model adjusted for gross domestic product, ecological footprint, and population, each 1 unit of the well-being scale was associated with an increase in life expectancy of 4.0 years (95% confidence interval = 2.7-5.3). In conclusion, better sense of well-being has a strong relationship with life expectancy regardless of economic status or population size, suggesting that governments should foster happiness in order to support long-living populations.