Grandparents who help and support their grandchildren live longer than the ones who do not, reveals a new study.
The study was published in the journal of Evolution and Human Behavior.
"It seems plausible that the development of parents' and grandparents' prosocial behaviour towards their kin left its imprint on the human body in terms of a neural and hormonal system," said first author Sonja Hilbrand, doctoral student in the Department of Psychology at the University of Basel.
"This subsequently laid the foundation for the evolution of cooperation and altruistic behaviour towards non-kin," Hilbrand added.
The team conducted survival analyses of over 500 people aged between 70 and 103 years, drawing on data from the Berlin Aging Study collected between 1990 and 2009.
They compared grandparents who provided occasional childcare with grandparents who did not, as well as with older adults, who did not have children or grandchildren but who provided care for others in their social network.
More From This Section
The results revealed that caregiving can have a positive effect on the mortality of the carers as half of the grandparents who took care of their grandchildren were still alive about ten years after the first interview in 1990.
The same applied to participants who did not have grandchildren, but who supported their children - for example, by helping with housework.
In contrast, about half of those who did not help others died within five years.
The researchers were also able to show that this positive effect of caregiving on mortality was not limited to help and caregiving within the family.
The researchers think that prosocial behavior was originally rooted in the family.
"But helping shouldn't be misunderstood as a panacea for a longer life," said Ralph Hertwig, Director of the Center for Adaptive Rationality at the Max Planck Institute for Human Development in the Germany.
"A moderate level of caregiving involvement does seem to have positive effects on health. But previous studies have shown that more intense involvement causes stress, which has negative effects on physical and mental health," Hertwig explained.