Do Green People Lead Happier Lives?

Do green people lead happier lives?

An article published by the Danish Ministry of the Environment looks into this question.

The short answer is it looks like there might be a link there.

They found that there was a circular relationship between sustainable behaviors and happiness. Happier people tend to live more sustainable lives and also, those who led sustainable lives were happier.

But there was a third thing that informed this happiness-sustainability link.

al·tru·ismˈaltro͞oˌizəm/ nounthe belief in or practice of disinterested and selfless concern for the well-being of others.
"some may choose to work with vulnerable elderly people out of altruism"
ZOOLOGYbehavior of an animal that benefits another at its own expense.
Is there a way to move large swaths of the population toward more ecological habits if they are very unhappy? 

Do you feel that your desires to make more sustainable choices make you happier? Do you do them out of a yearning to help the greater good, or does it come from a motivation rooted in personal advancement?