Although it sounds weird, evidence has accrued in population studies and in animal research that stressful prenatal experiences can predispose people to chronic diseases. Several studies have found that people who were in utero during famines are more likely to have cardiovascular disease, diabetes or the erosion of a key cognitive ability than those who were not. People who were exposed to the influenza epidemic of 1918 in early life were more likely to die of cardiovascular disease than people who were not. Studies in animals have shown that prenatal stresses can cause differences in how genes are expressed. The theory goes that those parental experiences shape the offspring’s metabolism in a way that responds poorly to a world that is not so strained.

Steckel and his graduate student, Garrett Senney, found evidence that the same thing may have happened in the South, when decades of post-Civil War poverty began to be reversed. Modern-day heart disease deaths were higher in states that experienced a rapid rise out of poverty between 1950 and 1980 — even when controlling for the effects of obesity, smoking and education level…

“In many cases, including the one in the South, people have suffered malnutrition as well as high levels of chronic toxic stress in their lives when people are faced with poverty,” Thornburg said. “Adaptations are made by the baby, but if the baby is faced with a diet of plenty … where it’s possible to get a lot of fat and sugar, those high-energy diets then are not well-received.”