Older people who help and support others live longer, found a multinational study. And grandparents who care for their grandchildren on average live longer than grandparents who do not.
The study was conducted by researchers from the University of Basel, Edith Cowan University, the University of Western Australia, the Humboldt University of Berlin, and the Max Planck Institute for Human Development in Berlin.
Older people who help and support others are also doing themselves a favour. An international research team has found that grandparents who care for their grandchildren on average live longer than grandparents who do not.
The researchers 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.
In contrast to most previous studies on the topic, the researchers deliberately did not include grandparents who were primary or custodial caregivers. Instead, 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.
The results of their analyses show that this kind of caregiving can have a positive effect on the mortality of the carers. 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 data analysis showed that childless older adults who provided others with emotional support, for example, also benefited. Half of these helpers lived for another seven years, whereas non-helpers on average lived for only another four years.
“But helping shouldn’t be misunderstood as a panacea for a longer life,” says Ralph Hertwig, director of the Centre for Adaptive Rationality at the Max Planck Institute for Human Development. “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,” says Hertwig. As it is not customary for grandparents in Germany and Switzerland to take custodial care of their grandchildren, primary and custodial caregivers were not included in the analyses.
The researchers think that prosocial behaviour was originally rooted in the family. “It seems plausible that the development of parents’ and grandparents’ prosocial behaviour toward their kin left its imprint on the human body in terms of a neural and hormonal system that subsequently laid the foundation for the evolution of cooperation and altruistic behaviour towards non-kin,” says first author Sonja Hilbrand, doctoral student in the department of psychology at the University of Basel.
Grandparenting has been proposed as an ultimate evolutionary mechanism that has contributed to the increase in human life expectancy (see the grandmother hypothesis). The neural and hormonal system – originally rooted in parenting and thus grandparenting – that is activated in the process of caregiving has been suggested as a potential proximate mechanism that promotes engagement in prosocial behavior towards kin and non-kin alike. Evidence and theory suggest that activating this caregiving system positively impacts health and may reduce the mortality of the helper. Although some studies have found grandparental care to have beneficial effects on grandparents' health outcomes, most studies have focused on the detrimental health consequences of providing custodial care for grandchildren. Little is known about how non-custodial grandparental and other forms of caregiving relate to mortality hazards for the care provider. Using an evolutionary framework, we examined whether caregiving within and beyond the family is related to mortality in older adults. Survival analyses based on data from the Berlin Aging Study revealed that mortality hazards for grandparents who provided non-custodial childcare were 37% lower than for grandparents who did not provide childcare and for non-grandparents. These associations held after controlling for physical health, age, socioeconomic status and various characteristics of the children and grandchildren. Furthermore, the effect of caregiving extended to non-grandparents and to childless older adults who helped beyond their families. Potential ultimate and proximate mechanisms underlying these effects are discussed.
Sonja Hilbrand, David A Coall, Denis Gerstorf, Ralph Hertwig