may be a way to protect later generations. Essentially, genetic changes train our descendants’ bodies through heredity rather than behavior. This suggests that what we call genetic defects may actually be ways to increase our descendants’ odds of survival in a potentially dangerous environment, by relaying hormonal information to the fetus in the womb.
The womb is itself an environment: a watery world of sounds, movement, and human biochemicals. Recent research suggests that, during the last trimester of pregnancy, fetuses in the womb can learn and remember just as well as newborns.16 Part of what they may learn, based on what their mothers go through during pregnancy, is whether the world outside the womb is safe and healthy or dangerous and toxic.
If the fetus’s mother is relatively happy and healthy during her pregnancy, and if she has a nervous system that is settled, her body will produce few stress hormones. As a result, by the time the fetus begins journeying down the birth canal, his or her body may have learned that the world is a generally safe and settled place to be.
But if the fetus’s mom experiences trauma, or if her earlier trauma causes a variety of stress hormones to regularly get released into her body, her baby may begin life outside the womb with less of a sense of safety, resilience, and coherence.
Zoë Carpenter sums this up in a simple, stark observation:
Health experts now think that stress throughout the span of a woman’s life can prompt biological changes that affect the health of her future children. Stress can disrupt immune, vascular, metabolic, and endocrine systems, and cause cells to age more quickly.17
All of this suggests that one of the best things each of us can do—not only for ourselves, but also for our children and grandchildren—is to metabolize our pain and heal our trauma. When we heal and make more room for growth in our nervous systems, we have a better chance of spreading our emotional health to our descendants, via healthy DNA expression. In contrast, when we don’t address our trauma, we may pass it on to future generations, along with some of our fear, constriction, and dirty pain.
Trauma hurts. It can fill us with reflexive fear, anxiety, depression, and shame. It can cause us to fly off the handle; to reflexively retreat and disappear; to do things that don’t make sense, even to ourselves; or, sometimes, to harm others or ourselves.
One of my mentors, Dr. Noel Larson, used to say, “If something is hysterical, then it is usually historical.” If your (or anyone’s) reaction to a current situation has more (or far less) energy than it normally would, then it likely involves energy from ancient historical trauma that has lost its context. In the present, your body is experiencing unmetabolized trauma from the past.
The same may be true if you respond with an uncharacteristically low amount of energy—for example, if you react to the news of a good friend’s death with a brief, flat “That’s too bad.” In this case, the ancient historical trauma has triggered a freeze response—what therapists call dissociation—rather than a fight or flight reaction.18 In either case, this trauma may have been passed down to you through your parents’ or other ancestors’ actions, through their DNA, or through both.
Sometimes the body couples and compounds this trauma with the energy of other traumatic events. This can cause people to suddenly and completely (though usually temporarily) lose their cool without having any idea why. Remember, to the traumatized body, all threats—current or ancient, individual or collective, real or imagined—are exactly the same. The lizard brain senses danger and commands the body to fight, flee, or freeze.
Trauma is unique to each body. What one person experiences as trauma, another may experience as nothing more than a big challenge. I’ve had clients who were beaten, raped, or deeply betrayed, yet who metabolized their pain and healed. I’ve had others who were traumatized by loud noises or the affection of unfamiliar, overeager dogs.
That said, most people experience trauma if an experience they have:
• Is unexpected (for example, the 2007 collapse of the 35W highway bridge in Minneapolis).
• Involves the death of many people, especially children (for example, the Tulsa race riot of 1921).
• Lasts a long time or repeats itself multiple times (such as Hurricane Katrina and its aftermath).
• Has unknown causes (for instance, when your partner suddenly and mysteriously disappears).
• Is deeply poignant or meaningful (such as the killing of twenty-seven people—twenty of whom were children between the ages of six and seven—at Sandy Hook Elementary School).
• Impacts a large area and/or many people (for example, an earthquake, a plague, a terrorist attack, persecution, or enslavement).
These are the effects of trauma involving specific incidents. But what about the effects of repetitive trauma: unhealed traumas that accumulate over time? The research is now in: the effects on the body from trauma that is persistent (or pervasive, repetitive, or long-held) are significantly negative, sometimes profoundly so. While many studies support this conclusion,19 the largest and best known is the Adverse Childhood Experiences Study (ACES), a large study of 17,000 people20 conducted over three decades by the Centers for Disease Control and Prevention (CDC) and the healthcare conglomerate Kaiser Permanente. Published in 2014, ACES clearly links childhood trauma (and other “adverse childhood events” involving abuse or neglect21) to a wide range of long-term health and social consequences, including illness, disability, social problems, and early death—all of which can get passed down through the generations. The ACE study also demonstrates a strong link between the number of “adverse childhood events” and increased rates of heart disease, cancer, stroke, diabetes, chronic lung disease, alcoholism, depression, liver disease, and sexually transmitted diseases, as well as illicit drug use, financial stress, poor academic and work performance, pregnancy in adolescence, and attempted suicide. People who have experienced four or more “adverse events” as children are twice as likely to develop heart disease than people who have experienced none. They are also twice as likely to develop autoimmune diseases, four and a half times as likely to be depressed, ten times as likely to be intravenous drug users, and twelve times as likely to be suicidal. As children, they are thirty-three times as likely to have learning and behavior problems in school.
Pediatrician Nadine Burke-Harris offers the following apt comparison: “If a child is exposed to lead while their brain is developing, it affects the long-term development of their brain . . . It’s the same way when a child is exposed to high doses of stress and trauma while their brain is developing . . . Exposure to trauma is particularly toxic for children.” In other words, there is a biochemical component behind all this.
When people experience repeated trauma, abuse, or high levels of stress for long stretches of time, a variety of stress hormones get secreted into their bloodstreams. In the short term, the purpose of these chemicals is to protect their bodies. But when the levels of these chemicals22 remain high over time, they can have toxic effects, making a person less healthy, less resilient, and more prone to illness. High levels of one or more of these chemicals can also crowd out other, healthier chemicals—those that encourage trust, intimacy, motivation, and meaning.
All of this suggests that trauma is a major contributor to many of our bodily, mental, and social ills, and that mending our trauma may be one of the most effective ways to address those ills.
The results of the ACE study are dramatic. Yet it covered only fifteen years. How much more dramatic might the results be for people who have experienced (or whose
