This book explores how the experiences of childhood shape us into the adults we become. Cutting-edge research tells us that what doesn’t kill you doesn’t necessarily make you stronger. Far more often, the opposite is true: the early chronic unpredictable stressors, losses, and adversities we face as children shape our biology in ways that predetermine our adult health. This early biological blueprint depicts our proclivity to develop life-altering adult illnesses such as heart disease, cancer, autoimmune disease, fibromyalgia, and depression. It also lays the groundwork for how we relate to others, how successful our love relationships will be, and how well we will nurture and raise our own children.
My own investigation into the relationship between childhood adversity and adult physical health began after I’d spent more than a dozen years struggling to manage several life- limiting autoimmune illnesses while raising young children and working as a journalist. In my forties, I was paralyzed twice with an autoimmune disease known as Guillain-Barré syndrome, similar to multiple sclerosis, but with a more sudden onset. I had muscle weakness; pervasive numbness; a pacemaker for vasovagal syncope, a fainting and seizing disorder; white and red blood cell counts so low my doctor suspected a problem was brewing in my bone marrow; and thyroid disease.
Still I knew: I was fortunate to be alive, and I was determined to live the fullest life possible. If the muscles in my hands didn’t cooperate, I clasped an oversized pencil in my fist to write. If I couldn’t get up the stairs because my legs resisted, I sat down halfway up and rested. I gutted through days battling flulike fatigue—pushing away fears about what might happen to my body next; faking it through work phone calls while lying prone on the floor; reserving what energy I had for moments with my children, husband, and family life; pretending that our “normal” was really okay by me. It had to be—there was no alternative in sight.
Increasingly, I devoted my skills as a science journalist to helping women with chronic illness, writing about the intersection between neuroscience, our immune systems, and the innermost workings of our human hearts. I investigated the many triggers of disease, reporting on chemicals in our environment and foods, genetics, and how inflammatory stress undermines our health. I reported on how going green, eating clean, and practices like mindbody meditation can help us to recuperate and recover. At health conferences I lectured to patients, doctors, and scientists. My mission became to do all I could to help readers who were caught in a chronic cycle of suffering, inflammation, or pain to live healthier, better lives.
In the midst of that quest, three years ago, in 2012, I came across a growing body of science based on a groundbreaking public health research study, the Adverse Childhood Experiences Study, or ACE Study. The ACE Study shows a clear scientific link between many types of childhood adversity and the adult onset of physical disease and mental health disorders. These traumas include being verbally put down and humiliated; being emotionally or physically neglected; being physically or sexually abused; living with a depressed parent, a parent with a mental illness, or a parent who is addicted to alcohol or other substances; witnessing one’s mother being abused; and losing a parent to separation or divorce. The ACE Study measured ten types of adversity, but new research tells us that other types of childhood trauma—such as losing a parent to death, witnessing a sibling being abused, violence in one’s community, growing up in poverty, witnessing a father being abused by a mother, being bullied by a classmate or teacher—also have a long-term impact.
These types of chronic adversities change the architecture of a child’s brain, altering the expression of genes that control stress hormone output, triggering an overactive inflammatory stress response for life, and predisposing the child to adult disease. ACE research shows that 64 percent of adults faced one ACE in their childhood, and 40 percent faced two or more.
My own doctor at Johns Hopkins medical institutions confessed to me that she suspected that, given the chronic stress I’d faced in my childhood, my body and brain had been marinating in toxic inflammatory chemicals my whole life—predisposing me to the diseases I now faced.
My own story was a simple one of loss. When I was a girl, my father died suddenly. My family struggled and became estranged from our previously tight-knit, extended family. I had been exceptionally close to my father and I had looked to him for my sense of being safe, okay, and valued in the world. In every photo of our family, I’m smiling, clasped in his arms. When he died, childhood suddenly ended, overnight. If I am honest with myself, looking back, I cannot recall a single “happy memory” from there on out in my childhood. It was no one’s fault. It just was. And I didn’t dwell on any of that. In my mind, people who dwelled on their

past, and especially on their childhood, were emotionally suspect.
I soldiered on. Life catapulted forward. I created a good life, worked hard as a science
journalist to help meaningful causes, married a really good husband, and brought up children I adored—children I worked hard to stay alive for. But other than enjoying the lovely highlights of a hard-won family life, or being with close friends, I was pushing away pain. I felt myself a stranger at life’s party. My body never let me forget that inside, pretend as I might, I had been masking a great deal of loss for a very long time. I felt myself to be “not like other people.”
Seen through the lens of the new field of research into Adverse Childhood Experiences, it suddenly seemed almost predictable that, by the time I was in my early forties, my health would deteriorate and I would be brought—in my case, quite literally—to my knees.
Like many people, I was surprised, even dubious, when I first learned about ACEs and heard that so much of what we experience as adults is so inextricably linked to our childhood experiences. I did not consider myself to be someone who had had Adverse Childhood Experiences. But when I took the ACEs questionnaire and discovered my own ACE Score, my story also began to make so much more sense to me. This science was entirely new, but it also supported old ideas that we have long known to be true: “the child is father of the man.” This research also told me that none of us is alone in our suffering.
One hundred thirty-three million Americans suffer from chronic illness and 116 million suffer from chronic pain. This revelation of the link between childhood adversity and adult illness can inform all of our efforts to heal. With this knowledge, physicians, health practitioners, psychologists, and psychiatrists can better understand their patients and find new insights to help them. And this knowledge will help us ensure that the children in our lives—whether we are parents, mentors, teachers, or coaches—don’t suffer from the long-term consequences of these sorts of adversity.
To learn everything I could, I spent two years interviewing the leading scientists who research and study the effects of Adverse Childhood Experiences and toxic childhood stress. I combed through seventy research papers that comprise the ACE Study and hundreds of other studies from our nation’s best research institutions that support and complement these findings. And I followed thirteen individuals who suffered early adversity and later faced adult health struggles, who were able to forge their own life-changing paths to physical and emotional healing.
In these pages, I explore the damage that Adverse Childhood Experiences can do to the brain and body; how these invisible changes contribute to the development of disease including autoimmune diseases, long into adulthood; why some individuals are more likely to be affected by early adversity than others; why girls and women are more affected than men; and how early adversity affects our ability to love and parent.
Just as important, I explore how we can reverse the effects of early toxic stress on our biology, and come back to being who we really are. I hope to help readers to avoid spending so much of their lives locked in pain.
Some points to bear in mind as you read these pages:
• Adverse Childhood Experiences should not be confused with the inevitable small challenges of childhood that create resilience. There are many normal moments in a happy childhood, when things don’t go a child’s way, when parents lose it and apologize, when children fail and learn to try again. Adverse Childhood Experiences are very different sorts of experiences; they are scary, chronic, unpredictable stressors, and often a child does not have the adult support needed to help navigate safely through them.
• Adverse Childhood Experiences are linked to a far greater likelihood of illness in adulthood, but they are not the only factor. All disease is multifactorial. Genetics, exposures to toxins, and infection all play a role. But for those who have experienced ACEs and toxic stress, other disease-promoting factors become more damaging. To use a simple metaphor, imagine the immune system as being something like a barrel. If you encounter too many environmental toxins from chemicals, a poor processed-food diet, viruses, infections, and chronic or acute stressors in adulthood, your barrel will slowly fill. At some point, there may be one certain exposure, that last drop that causes the barrel to spill over and disease to develop. Having faced the chronic unpredictable stressors of Adverse Childhood Experiences is a lot like starting life with your barrel half full. ACEs are not the only factor in determining who will develop disease later in life. But they may make it more likely that one will.
• The research into Adverse Childhood Experiences has some factors in common with the research on post-traumatic stress disorder, or PTSD. But childhood adversity can lead to a

far wider range of physical and emotional health consequences than the overt symptoms of post-traumatic stress. They are not the same.
• The Adverse Childhood Experiences of extreme poverty and neighborhood violence are not addressed specifically in the original research. Yet clearly, growing up in unsafe neighborhoods where there is poverty and gang violence or in a war-torn area anywhere around the world creates toxic childhood stress, and that relationship is now being more deeply studied. It is an important field of inquiry and one I do not attempt to address here; that is a different book, but one that is no less important.
• Adverse Childhood Experiences are not an excuse for egregious behavior. They should not be considered a “blame the childhood” moral pass. The research allows us to finally tackle real and lasting physical and emotional change from an entirely new vantage point, but it is not about making excuses.
• This research is not an invitation to blame parents. Adverse Childhood Experiences are often an intergenerational legacy, and patterns of neglect, maltreatment, and adversity almost always originate many generations prior to one’s own.
The new science on Adverse Childhood Experiences and toxic stress has given us a new lens through which to understand the human story; why we suffer; how we parent, raise, and mentor our children; how we might better prevent, treat, and manage illness in our medical care system; and how we can recover and heal on a deeper level than we thought possible.
And that last bit is the best news of all. The brain, which is so changeable in childhood, remains malleable throughout life. Today researchers around the world have discovered a range of powerful ways to reverse the damage that Adverse Childhood Experiences do to both brain and body. No matter how old you are, or how old your children may be, there are scientifically supported and relatively simple steps that you can take to reboot the brain, create new pathways that promote healing, and come back to who it is you were meant to be.
To find out about how many categories of ACEs you might have faced when you were a child or teenager, and your own ACE Score, turn the page and take the Adverse Childhood Experiences Survey for yourself.