Researching the Hunger Winter
A Calvin College psychology professor’s professional participation in an international study on the Dutch hunger winter—known in the Netherlands as the Hongerwinter—has a personal motivation.
Julie Yonker's areas of expertise include both cognitive aging and teratology, the study of birth defects. So the idea of studying what happened cognitively to babies conceived and born during the famine in the Netherlands that came at the end of World War II, in late 1944 and early 1945, was appealing to her instincts as a researcher. But more than that, the story of her own mother, Irene, drove her to first get involved in the project.
"My mom was a very young child during the famine," she said, "and she died of breast cancer at an early age.” While researching the Hunger Winter on the internet, Yonkers discovered a team of researchers in the Netherlands who had found the children born in that country during the famine had high rates of cancer. “I immediately contacted them and asked if I could join their work,” she said.
Media interest
Now, Yonker, a Calvin psychology professor, collaborates with the Dutch Hunger Winter Birth Cohort Study investigators, bringing her particular expertise in cognitive aging and teratology to the group's research. She has traveled to the Netherlands to study the impact of prenatal malnutrition on adult cognitive function.
The team's most recent findings are due out this fall in the print version of the Proceedings of the National Academy of Sciences, one of the world's most-cited scientific serials. But already the results are garnering considerable media interest, with September stories on the BBC, Voice of America, Discover Magazine and others.
A host of diseases
Those media outlets seized on a key finding in the Amsterdam-based group's latest conclusions—findings based on a longitudinal study going back to the mid 1960s: children conceived and born during the hunger winter seem to be at a higher risk for cognitive decline, likely leading toward Alzheimer's, in addition to suffering other health-related diseases such as diabetes, heart attacks, high blood pressure and cancers in greater numbers than children born both before and after the hunger winter.
Yonker, who has a Ph.D. in cognitive and experimental psychology from Stockholm University in Sweden, is not surprised.
"The famine saw pregnant mothers trying to exist on somewhere between 400 and 800 calories a day," she said, "and we suspect that in many cases they did with less than that because they often gave some of their food to their other children. The loss of life due to the famine was apparent at the time (almost 20,000 people died) and increased mortality rates continue to this day. It was a terrible and tragic time for the country."
Bittersweet project
The Hunger Winter followed the Battle of Normandy in the summer of 1944, when conditions in the Netherlands, still occupied by the Nazis, deteriorated. Several events—a Dutch railway strike, an embargo on food transports to the western Netherlands by the German government, frozen canals as a result of an early winter and the failure of Operation Market Garden—all colluded to quickly deplete the food supplies in the western provinces of the country.
That winter, people walked miles for any sort of food, even eating things like tulip bulbs when nothing else could be found.
"I can't imagine what they went through, even though I’ve heard some of the stories," Yonkers said. "Never before had a previously well-nourished country encountered a short-duration famine only to return to a well-nourished state. Yet this terrible event has provided a unique opportunity to examine the long-term impacts of prenatal malnutrition. So maybe, in some small way, our work can bring some good to what was truly a tragedy."
Helping women
Yonker said the work has numerous scientific and health implications. “It also has substantial practical applications,” she added. “Many women suffer from extreme morning sickness during the first trimester, which can lead to metabolic changes in the mother similar to those seen in starvation."
She noted that the meticulous Dutch record-keeping also is a boon for researchers.
"Despite the adversities of war," she said, "Dutch doctors and midwives offered professional obstetric care, and there are detailed records on course of pregnancy, delivery, size and health of the baby at birth, plus records of food rations."
Study goes on
The team plans to continue studying the famine babies for as long as possible, hoping in the next wave of testing to include additional cognitive measurements. Yonkers is gratified that her work can, in some small way, serve as a testament to the life and legacy of her mother:
"I would not have gotten involved with this research if my mom had not contracted breast cancer," she said. "I'm not a cancer researcher, so I couldn't redeem that part of my mom's story, but I have tried to use the gifts, talents and education God has provided me to redeem the areas that I am able—learning more about how the prenatal environment can have vast long-term consequences. So, this too becomes for me an amazing story of God's hand on this redemptive work."