Decades of research shows that experiencing traumatic things as a child—such as having an alcoholic parent or growing up in a troubled home—puts you at risk for poor health and survival later in life.
But mounting evidence suggests that establishing strong social relationships can help mitigate these effects. Not just for people, but for our cousins, too.
Drawing on 36 years of data, a new study of nearly 200 baboons in southern Kenya finds that adversities early in life can take years off their lives, but strong social bonds with other baboons in adulthood can help restore them.
“It’s like the old saying from the King James Apocrypha, ‘A faithful friend is the medicine for life,'” said senior author Susan Alberts, professor of biology and evolutionary anthropology at Duke University.
Baboons who had a difficult childhood were able to regain two years of life expectancy by making strong friends.
The results appear May 17 in the journal Nature Science advances.
Research has consistently found that those who go through more bad experiences growing up — things like abuse, neglect, a mentally ill parent — are more likely to face an early grave in the future. But figuring out how one leads to the other has been much more difficult.
While the downsides of difficult breeding are well documented, Alberts said, “the underlying mechanisms have been much more difficult to pin down.”
A limitation of previous research was the reliance on people’s self-reported memories of their past, which can be subjective and inaccurate.
This is where long-running research on wild primates — which share more than 90 percent of our DNA — comes in, Alberts said. Since 1971, researchers have followed individual baboons near Amboseli National Park in Kenya on an almost daily basis, noting which animals they socialize with and how they have achieved success over their lives as part of the Amboseli Baboon Research Project.
In the new study, the researchers wanted to know: How do early life adversities ultimately lead to early death, even years later?
One hypothesis is that trauma survivors often grow up with troubled relationships as adults, and the resulting lack of social support, in turn, shortens their lives. But the new findings paint a different picture of the causal pathway involved in the baboons, and offer some hope.
In the study, the researchers looked at how early life experiences and adult social connections affected long-term survival in 199 female monkeys closely monitored in Amboseli between 1983 and 2019.
Baboons don’t thrive in broken or dysfunctional homes per se, but they are no strangers to hardship. For each female, the team recorded their exposure to six potential sources of early adversity. They looked at whether her mother was inferior or socially isolated, or whether her mother had died before she reached adulthood. They also noted if she was born in a drought year, was born in a large group or had a sibling close in age, which could mean more competition for resources or maternal attention.
The results show that for baboons that grew up in the semi-arid and unpredictable area of Amboseli, stressful experiences are common. Of the baboons in the study, 75% experienced at least one stressor, and 33% experienced two or more.
The analyzes also confirmed previous findings that the more hardships a female experienced, the shorter her lifespan. This wasn’t just because the baboons that experienced more disruptions early in life were more socially isolated as adults, Alberts said, it was also the case.
Instead, the researchers were able to show that 90% of the decline in survival was due to the direct effects of early adversity, rather than to the poor social connections they inevitably experience in adulthood.
The influences add up. Each additional suffering translated into a loss of 1.4 years of life, no matter how strong or weak their bonds with other baboons were. Baboons who had four bad experiences growing up died about 5.6 years earlier than those who didn’t experience any—a significant drop considering the average lifespan of a female baboon is just 18 years.
But that doesn’t mean that baboons that had an unfortunate start in life are doomed to a short life.
“Women who had bad early lives don’t have a destiny,” said first author Elizabeth Lange, assistant professor at SUNY Oswego.
far from it. The researchers also discovered that the baboons that formed stronger social bonds — measured by how often they cuddled with their closest friends — added 2.2 years to their lives, regardless of what they encountered when they were younger.
Baboons whose mothers died before they reached adulthood, but then established strong friendships in adulthood, were the most able to recover.
Alberts said the other side is also true. “Strong social ties can mitigate the effects of early life adversities, but conversely, weak social ties can amplify them.”
The researchers cannot determine whether the findings are generalizable to humans. But if this is the case, say the researchers, it would indicate that early intervention is not the only effective way to overcome the effects of childhood trauma.
“We found that both early life adversity and adult social interactions influence survival independently,” Lang said. “This means that interventions that occur throughout the life course can improve survival.”
In other words, it can help to focus on adults, especially their ability to build and maintain relationships.
“If you had adversity early in life, whatever you did, try to make friends,” Alberts said.
This research was supported by grants from the National Institutes of Health (R01AG053308, P01AG031719, R01AG053330, R01AG071684, R01HD088558 and R01AG075914) and from the National Science Foundation (1456832)