Epigenetic changes often serve to biologically prepare offspring for an environment similar to that of the parents, Yehuda explains. In this case, however, the needs of the fetus seem to have trumped that goal. With low levels of cortisol and high levels of the enzyme that breaks it down, many descendants of Holocaust survivors would be ill adapted to survive starvation themselves. In fact, that stress hormone profile might make them more susceptible to PTSD (below, yellow); previous studies have indeed suggested that the offspring of Holocaust survivors are more vulnerable to the effects of stress and are more likely to experience symptoms of PTSD. These descendants may also be at risk for age-related metabolic syndromes, including obesity, hypertension and insulin resistance, particularly in an environment of plenty.