The happier you are in old age, the longer you live, finds a new study.

It’s the latest in a string of recent research that is starting to make clear just how important joy is to good health. The most famous of these studies, the Harvard Study of Adult Development, followed its participants for 80 years and found relationship happiness, specifically, to be critical to longevity.

“The surprising finding is that our relationships and how happy we are in our relationships has a powerful influence on our health,” said Robert Waldinger, the study’s director, in 2017 when the long-running research reached this conclusion. “Taking care of your body is important, but tending to your relationships is a form of self-care too. That, I think, is the revelation.”

But like so much research, the findings from the Harvard study were based on an entirely American, and male, sample of people. Which is why the newest study is so notable. Published in Age and Ageing, the study looked at happiness halfway around the world, by examining national survey data of nearly 4,500 Singaporeans, aged 60 and older.

The surveys, administered in 2009, included questions about happiness. For instance, participants answered whether, in the past week, they had experienced the following: ‘I felt happy,’ ‘I enjoyed life’ and ‘I felt hope about the future.’ During the analysis, researchers assigned participants to one of two groups — either an overall ‘Happy’ or ‘Unhappy’ group — as well as developed an individualized, more nuanced ‘happiness score.’ The researchers controlled for the possible influence of a variety of demographic, health and social factors, as well as lifestyle choices, health and social factors.

The researchers then looked at mortality — specifically, which of the participants had passed away by the end of 2015. Among the ‘Happy’ older people, 15% had passed away at some point in that 6-year span; among the ‘Unhappy’ elderly, 20% had passed away.

But more telling was the breakdown of the individualized ‘happiness scores’ — the researchers found that for every one-point increase on the happiness score, the chance of death reduced by 9%. Ultimately, the likelihood of dying from any cause was 19% less likely for happy older people than for the unhappy. This held true for both men and women, and across ages.

“The findings indicate that even small increments in happiness may be beneficial to older people’s longevity,” said senior author Rahul Malhotra, head of research at the Centre for Ageing Research and Education, a partnership between Duke University in the US and the National University of Singapore.”Therefore individual-level activities as well as government policies and programs that maintain or improve happiness or psychological well-being may contribute to a longer life among older people.”

Amid a loneliness epidemic across the world, studies like this suggest the antidote — and indeed, maybe the secret to a longer, healthier live — is universal, too.