The research, published in the journal BMC Public Health, also found doing badly in the contest was associated with a greater increase in life satisfaction compared to not taking part at all.
The team, who were surprised to find the result, say the research chimes with previous studies that show success in big events, such as sporting fixtures, can boost a nation's health and wellbeing.
Dr Filippos Filippidis, lead author of the research from the School of Public Health at Imperial, said: "This finding emerged from a jokey conversation in our department. Our 'day job' involves investigating the effect of public policies, environmental factors and economic conditions on people's lifestyle and health. Our department employs people from lots of different countries and around the time of the Eurovision Song Contest we were chatting about whether the competition could also affect a country's national wellbeing. We looked into it and were surprised to see there may be a link."
The researchers analysed data from over 160,000 people from 33 European countries. All the people completed a questionnaire as a part of a survey called the Eurobarometer, which is conducted several times each year by the European Commission. Among other things, the survey asks people how satisfied they feel with their life.
The team, who analysed data collected around the time of the Eurovision Song Contest (May and June) between 2009-2015, found that people reported being more satisfied with their life if their country had done well in the Eurovision Song Contest that year.
The researchers then calculated an increase of 10 places on the final scoreboard - e.g. if a country finished 2nd instead of 12th - was associated with a four per cent higher chance of being satisfied with life. However, winning the competition was not associated with an additional increase in life satisfaction.
The scientists then compared data from countries who participated but did badly, to countries who didn't take part at all. They found that taking part but finishing near the bottom of the table was associated with a 13 per cent higher chance of life satisfaction compared to not taking part in the competition.
The team stress the research only shows there is an association - rather than directly showing the contest is responsible for raising life satisfaction. However, Dr Filippidis says the work highlights the possible impact of big events on a nation's psyche.
"Previous work, by other teams around the world, has shown that national events may affect mood and even productivity - for instance research suggests an increase in productivity in the winning city of the US Super Bowl."
He added that doing well in Eurovision or even just being part of it gives people something positive to discuss - rather than more negative events in the news.
"It increases the amount of good feeling around, even among people who are not particularly interested in the competition. I remember when Greece won in 2005 - in the weeks that followed people seemed to be in a better mood."
He added: "Our research shows that science can be used to test unexpected questions, but more importantly we hope it will encourage people to consider how our wellbeing, and consequently our health, can be influenced by a range of factors in the public sphere."
But he admits he wouldn't call himself a fan of the competition.
"I've been known to occasionally watch it in previous years. It's certainly entertaining, but I don't take it too seriously."
Source: Imperial College London
Full bibliographic information
'' Euphoria" or "Only Teardrops"? Eurovision Song Contest performance, life satisfaction and suicide" by F. Filippidis & A. Laverty et al. was published in BMC Public Health, May 11 2018