Generational Trauma: How Stress Gets Passed Down |
My parents are fairly anxious people. They are always 10 minutes early to every event and are typically sitting at the airport terminal 2 hours before boarding a flight. My brother and I inherited this trait and have dealt with anxiety for most of our childhood and adult lives.
It’s easy to recognize that anxiety can be passed down to us from our parents, whose parents (my grandparents) were probably also somewhat anxious like their parents before them. But recently, researchers have been interested in the generational transmission of more serious types of stress, or what some might call trauma. This isn’t the type of stress that just makes you chronically early for appointments; I’m talking about the type of stress that results from threats of death, serious injury, or sexual violence—stress that can affect someone’s mental health for their entire lives.
Although the term was first coined back in 1966, you hear a lot about generational trauma in the headlines lately. Generational trauma is the psychological and emotional effects of traumatic events passed down through generations, impacting people who did not directly experience the original event. The term was first used in the 1960’s when researchers observed the high rates of psychological distress experienced not just by Holocaust survivors, but also by the children of Holocaust survivors, who weren’t even conceived until after the end of World War II. How is this possible? How does trauma get passed down over the course of generations?
There are actually a lot of ways this can happen. The most intuitive is through parenting behaviors. Let’s imagine a parent has gone through some kind of trauma, like losing a child. You can imagine that losing a child—from an illness, accident, or for any reason at all—will likely affect the way a parent interacts towards their other children or even their other loved ones. If I lost someone in a car accident, for example, I might become incredibly overprotective about what my children can and cannot do, especially when it comes to riding in cars. My children would then likely become accustomed to anxiety around cars, or even anxiety about leaving the house more generally. Years later, when my children then have children of their own, they will likely use the same norms and values they were raised with to raise their own children, including anxiety around cars.
The opposite can also be true, in cases where parents don’t talk about their trauma and it becomes a source of anxiety because of the silence that is always lingering. This can happen with war trauma, where veterans refuse to discuss their experiences on the front lines. Indeed, after generational trauma was observed in the children of Holocaust survivors, it was identified in the children of Vietnam veterans, who were assumed to experience negative effects from living under the same roof as a traumatized individual (Yehuda & Lehrner, 2018).
Then there is generational trauma that exists because the conditions that caused the original trauma still linger. Issues like poverty and discrimination that resulted from slavery, or the displacement of Native American communities, for example, still exist today, even though slavery and colonization ended before any of us were born. Thus, even though the original trauma happened over a century ago, the effects remain for existing generations of Black and Native American people because of the lingering effects of discrimination that resulted from the original trauma.
Finally, there is one kind of generational trauma that persists without us even knowing it—the effect of trauma on epigenetics. Epigenetics are the set of heritable changes to the human genome that can be caused by environmental events. The most famous example is from the offspring of the Dutch Famine, when the Nazis blocked food supplies to the Netherlands during World War II.
During this time, no one in the Netherlands had enough to eat, including women unlucky enough to be pregnant at the time. When the war was over, most of these fetuses were born into an environment where there was finally enough to eat. But, having a prenatal environment where food was scarce produced a fetus that was prepared for a post-natal environment where food was also scarce. This created a body that was optimized to maintain as much fat as possible and to be more resistant to insulin.
Because of these changes, when food was again readily available, these individuals were better able to metabolize food and store fat, leading to adults who were at a higher risk for obesity, diabetes, and heart disease. Most importantly, these genetic changes were passed on to later generations, and not only were the children of mothers who experienced famine at high risk for these conditions, but so were their grandchildren, demonstrating how epigenetic effects of malnutrition can be passed down generationally.
The effects of severe psychological trauma can affect our stress system in the same way: When a pregnant mother experiences trauma, it changes the stress hormones in her body in a way that signals to the fetus that the post-natal environment is stressful and risky. Thus, you end up with a baby who is optimized for a stressful world—someone who is highly reactive to changes in the environment and has difficulty properly regulating their emotional responses. While this is adaptive in a stressful environment, it causes long-term mental health problems in a more stress-free world.
The moral of the story is that trauma does not only affect the individuals who experience it directly, but it can also get into the mind and under the skin of future generations. In fact, one recent study examining the offspring of Holocaust survivors is still documenting biological effects of the trauma three and four generations later (Oren et al., 2025). This means that interventions to help individuals who are experiencing trauma are incredibly important for their own well-being, and for the well-being of their families for generations to come.
Oren, G., Shoshani, A., Samra, N. N., Verbeke, W. J., Vrticka, P., Aisnberg-Shafran, D., & Ein-Dor, T. (2025). From trauma to resilience: psychological and epigenetic adaptations in the third generation of holocaust survivors. Scientific Reports, 15(1), 26193.
Yehuda, R., & Lehrner, A. (2018). Generational transmission of trauma effects: putative role of epigenetic mechanisms. World psychiatry, 17(3), 243-257.