The study, by researchers at the Karolinska Institute (KI) medical university in Stockholm, looked at 1.4 million Swedes born between 1911 and 1925. The researchers calculated that at the age of 60, the remaining life expectancy of men without children could be projected as a further 18.4 years, while those who had kids could expect 20.2 years more.
Women of the same age who did not have children could expect 23.1 more years, while those who did were likely to live another 24.6 years on average.
The study also showed that the positive effects of having children on life expectancy increased the older those in the sample got.
"There are several other studies on the subject and a large consensus that parents live longer than those who do not have kids, but not so many that follow parents through the years, nor look at how the effects of having kids impacts mortality at different ages," KI assistant professor of epidemiology Karin Modig told The Local.
Readers who aren't planning on having kids shouldn't worry too much just yet however.
The study's conclusions did not take into account other potentially important factors which may have impacted the sample group of people without children. Choosing not to have children due to health issues, for example, is one of them.
"We still don't know exactly what mechanisms the link works through. The childless group is a heterogeneous group which consists of both highly educated, generally healthy individuals, and individuals with poorer health. There are so many different reasons for not having children," Modig noted.
"However, there are several studies which show the need for support from a family member when you get older. So it's maybe more of a question for the health sector to consider. In other words, to give particular attention to those individuals."
The researchers say the study shows that social support from adult children grows in importance as we get older.
So could that be one reason why people in Mediterranean countries like Spain – where caring for older relatives is still a social norm – tend to be the best performers when it comes to life expectancy in Europe?
"It's difficult to say. The effects of having children on your risk of dying as you get old are still relatively small in comparison to other factors. But we actually have an extension of the project where we will also look at other, more family-based societal structures of health and social care," Modig revealed.
The study also looked at whether being married had an impact on mortality, and found that there was some difference for men, but not a significant difference for women. One reason for that could be that among the generation in the sample, unmarried men were generally a more socially vulnerable group, with a lesser level of education.