During World War II, the Finnish government evacuated about 70,000 children to protect them from the danger, stress and uncertainty of war. Their parents agreed to send them to foster homes primarily in Sweden. It was one of the largest evacuations of children in the 20th century. And years later, some would consider the program a grave mistake.
After the fighting stopped in 1945, the children began to return home. Beginning in the mid-1990s, scientists at the University of Helsinki caught up with some of these “war children,” now elderly adults, to examine how, if at all, the childhood separation from their parents had affected their health and well-being.
This research, which is ongoing, helps us understand the long-term consequences of another mass separation of children from their parents — the one orchestrated by the Trump administration.
More than 2,500 migrant children were taken from their parents and detained. Most have since been reunited, but 12,800 migrant children — a record, as we learned last week — remain in detention. Many are teenagers who crossed the border unaccompanied. In the past they typically would have been released in a timely fashion to sponsors — often parents or other family members who’d come here before them — but no longer.
How will this continued separation affect them? Judging from the Finnish experience, it may make the younger kids among them in particular sicker, stunt their cognitive development, and increase their risk of mental health problems for decades to come.
The Finnish children ranged from babies to 9-year-olds. Some were separated from their parents for more than six years, some for less than one; the average was nearly two years. Men evacuated as children, Finnish scientists found, were more likely to have mental health and substance abuse problems than men who weren’t. Both sexes were more likely to suffer from depression if separated.
There were also differences in cognitive ability. As part of its program of compulsory military service, Finland gave conscripts mathematical, verbal and visuospatial tests. Men sent away as children scored lower on these tests, particularly if separated as toddlers. But this held only if they were gone for more than a year. If less than a year, they scored the same as those who hadn’t been separated at all, suggesting that there is a threshold of time away from parents after which damage begins to accrue.
Some of these differences were expected, Johan Eriksson, the principal investigator on this research, told me in an email. Previous studies already indicated that early-life trauma could increase the risk of psychiatric disorders. But the Finnish scientists were surprised to observe differences in chronic disease risk as well. Illness and death from heart disease were more common in the separated group. They had about twice the risk of heart disease and a 40 percent increased risk of Type 2 diabetes. They had slightly higher blood pressure — particularly women. And women in the separated group reached puberty earlier, an acceleration of reproductive readiness that some hypothesize results from threatening, uncertain environments. (It’s also seen among girls with absent biological fathers.)
What biological mechanism might explain these differences? Animal studies indicate that chronic stress early in life can permanently reprogram the stress response, activate inflammatory pathways and increase vulnerability to various diseases. And Dr. Eriksson and his colleagues observed that, more than six decades after the war, those who had been evacuated still showed elevated baseline levels of cortisol, a stress hormone, compared to a control group.
Most of these differences weren’t huge, hinting that kids do possess some of the resilience we like to think they have. And, as with any observational study, it’s difficult to eliminate all confounders. The researchers know very little about the children’s foster homes, for example. Many foster families were well-to-do, so perhaps the children ate too well: A high-fat diet while living abroad could explain some of the associations scientists now observe, Dr. Eriksson told me. Another possibility is that families willing to send their children away exhibited some other trait that could explain why those children grew up to be less healthy.
Of course, animal studies, which aren’t as easily confounded as observational studies, have clearly shown that early-life stress can change how animals’ bodies work in adulthood. And parallel research on people who’ve been abused, neglected or bullied as children suggests that bad early-life experiences can leave their mark on our bodies, changing how genes are expressed over a lifetime.
Yet judging from narrative histories, many of the Finnish children ended up with decent surrogate parents. Why didn’t this soften the trauma of losing their biological parents? Maybe it did, but perhaps the trauma of losing one’s parents at a young age is so severe that it never completely heals. And some children may have been doubly traumatized: After integrating into a new family and culture — and, in some cases, forgetting how to speak Finnish altogether — they returned to biological parents who were now strangers.
The broader point is this: If the Finnish kids, who were sent away for their own well-being, and who often ended up in friendly households, have an elevated risk of disease decades later, what will happen to the migrant children warehoused in group homes and corralled behind chain-link fences? Their detention has been, on average, shorter than that of the Finnish kids, and many are older, but troubling stories are beginning to emerge from parents reunited with their children. Some children are anxious and withdrawn; they’ve occasionally regressed. They’re not the same kids their parents remember.
The Trump administration probably intended the separation of children from their parents to be cruel. Conceived as a deterrent, it was meant to hurt. But was it supposed to impair cognitive development and cause heart attacks, diabetes and mental illness decades later? This may be its more sinister legacy: a subtle but lifelong derangement of mind and body.
Moises Velasquez-Manoff, the author of An Epidemic of Absence: A New Way of Understanding Allergies and Autoimmune Diseases, is a contributing opinion writer.