In 2007, pediatrician Nadine Burke Harris, MPH ’02, set out on an idealistic mission: to deliver quality medical care to one of San Francisco’s poorest and most underserved neighborhoods—Bayview-Hunters Point, in the isolated southeastern corner of the city. Before Burke Harris arrived on the scene, only one pediatrician was serving the neighborhood’s 10,000 children. The community’s plight was starkly apparent in its ZIP code. In 17 of 21 other ZIP codes in the city, ischemic heart disease was the leading cause of early death. In three ZIP codes, HIV/AIDS was the leading cause. But in only one ZIP code—Bayview-Hunters Point—was violence the top killer.
Burke Harris founded the Bayview Child Health Center with the goal of tackling disparities in access to care, immunization rates, and asthma hospitalization rates. But she quickly discovered that the challenge was more deep-rooted than standard public health statistics would suggest. Her young patients often didn’t fit conventional diagnostic criteria. A 7-year-old named Diego, for example, had stopped growing at age 4, for no apparent reason. He also suffered from asthma, eczema, and behavior problems. Probing further, Burke Harris learned that Diego had been sexually molested at the age of 4—the year his normal growth came to a halt. The discovery made her stop in her tracks. Could all of Diego’s ostensibly separate medical problems be traced to a single early trauma?
Burke Harris soon found out that many of her patients with inexplicable chronic conditions—from attention deficit disorder and depression to asthma and hair loss—had suffered profound trauma in their young lives. The daily but often hidden struggles of life in Bayview-Hunters Point—which include violence and domestic abuse, substance use disorders and mental illness—were leaving lasting imprints on the bodies and minds of her young patients.
That realization shaped her career—and is today fueling a revolution in medicine and public health. In 2012, Burke Harris became founder and CEO of the Center for Youth Wellness in Bayview-Hunters Point. Its purpose was and is to improve the way pediatric clinics respond to adverse childhood experiences, or ACEs, to translate the most current science to the clinic, and to build a national movement for universal ACE screening. In 2014, the mediagenic physician delivered a dynamic TED Talk on the subject, which has garnered more than 6 million views. In 2018, Burke Harris published The Deepest Well: Healing the Long-Term Effects of Childhood Adversity, a clear-eyed and highly readable exploration of both the science and the human toll of ACEs.
Then, in February 2019, California Governor Gavin Newsom appointed Burke Harris the state’s first surgeon general—only the fifth state surgeon general in the country—tasked primarily with addressing childhood adversity. As she told a Vice reporter last July, with her signature blend of determination and disarming humor, “I am not a surgeon general who is going to just tell people to eat right and exercise.”
With the California post, Burke Harris’ platform expanded dramatically. But while the revolution she envisions is now underway, the goal is nowhere in sight. As she told The New York Times in 2018, “When you look at any successful public health campaign, it starts with raising awareness, so that people understand there is a problem to begin with. ACEs cross every line—racial, ethnic, geographic, gender, socioeconomic. Today, most parents are aware that secondhand smoke is really bad for kids, everyone has to wear a seat belt, and lead is a neurotoxin. We need a national public campaign about toxic stress. We need to be shouting this from the rooftops.”
The Science of ACEs
In 1998, the American Journal of Preventive Medicinepublished a groundbreaking collaborative study by the California health maintenance organization (HMO) Kaiser Permanente and the U.S. Centers for Disease Control and Prevention (CDC). Researchers had followed more than 17,000 Kaiser HMO members in the San Diego area, each of whom received a thorough medical exam and later filled out a questionnaire asking them about their history of childhood adversity. The questionnaire’s list of 10 adverse exposures reads like a modern compendium of formative hurt: emotional abuse, physical abuse, sexual abuse, physical neglect, emotional neglect, substance abuse in the household, mental illness in the household, having a mother who was treated violently, divorce or parental separation, and having criminal behavior in the household, including a family member going to prison.
Far from being a poor or marginalized population, the study subjects were middle and upper class, and 69 percent Caucasian; 74 percent had attended college. For that reason alone, the results were eye-opening. Sixty-seven percent of the patients reported at least one adverse experience by the age of 18, and 12.6 percent reported four or more. The study also found a clear dose-response connection between early trauma and the leading causes of adult mortality and morbidity: The greater the exposure to early adversity, the higher the risk of later illness. Compared with people with no ACEs, those with four or more were twice as likely to have heart disease or cancer, four times as likely to have emphysema or chronic bronchitis, and 12 times as likely to have attempted suicide.
Even more surprising, these disease risks were not necessarily tied to risky behaviors such as smoking, drinking, or overeating. In many cases, patients who had high ACE scores but abstained from cigarettes, alcohol, or excess calories nevertheless faced elevated risk for heart disease and other lethal conditions. Health-harming behaviors, it turned out, accounted for only 50 percent of the increased disease risk in adults.
Put simply, early adversity appeared to seep into the patients’ body cells, becoming lifelong biology.
Burke Harris first read the original ACE study in 2008, 10 years after it had come out. It was a moment of awakening. “The thing that I found most shocking was that I had never learned about ACEs in medical school or residency,” she says. “Looking at the associations—understanding that a person who has four or more ACEs has more than twice the risk of heart disease, which is the number-one killer in the United States of America—for me, that was astounding,”
After poring over all of the first decade of ACEs literature, Burke Harris decided to formally study her own patients at Bayview-Hunters Point. Her findings mirrored those already published. Just over 67 percent of the children had experienced one or more ACEs and 12 percent had four or more. Higher ACE scores were likewise correlated with higher risks of what often turn out to be lifelong conditions. Her patients with four or more ACEs were twice as likely to be overweight or obese, and 32.6 times as likely to have been diagnosed with learning and behavioral problems, compared with patients with no ACEs.
In her TED Talk, Burke Harris expanded on the implications of these findings, giving a nod to her education at the Harvard T.H. Chan School of Public Health. She also invoked one of the milestones in public health history—John Snow’s 1854 discovery that a vicious outbreak of cholera in London was caused by contaminated well water drawn by a street pump. After Snow presented his findings to authorities—an early tour de force in epidemiology—the pump handle was removed and the outbreak halted. As Burke Harris bluntly told the audience: “One of the things they teach you in public health school is that if you’re a doctor and you see 100 kids that all drink from the same well, and 98 of them develop diarrhea, you can go ahead and write that prescription for dose after dose after dose of antibiotics—or you can walk over and say, ‘What the hell is in that well?’”
The Biology of Adversity
Since the original 1998 ACE study, scientists have started to figure out the biological impacts of early toxic stress. They now know that when children are exposed to severe, frequent, or prolonged trauma without support from nurturing adults, the architecture and functioning of their developing brains are disrupted. Childhood adversity skews the normal “fight or flight” stress response triggered by adrenaline, impairing the brain’s ability to regulate its emotions and rein in impulses, and making the child hypervigilant to threats. Early adversity also alters the immune system, leading to chronic inflammation and vulnerability to autoimmune diseases such as asthma, rheumatoid arthritis, or lupus.
Adversity even alters how our cells’ genetic code is read and transcribed. While DNA is the basic blueprint for biology, environment and experience play a role in determining which parts of the genome are turned on and off. That’s because our cells contain both our genome and the epigenome, a layer of chemical markers that sit on top of our DNA and orchestrate which genes get read and transcribed into proteins and which don’t. When the stress response is chronically activated, these epigenetic markers are changed.
Perhaps most crucial, just as DNA is handed down from parent to child, so are these altered epigenetic markers—forging a biological chain of inheritance in which the calamitous physical and emotional effects of early adversity pass from one generation to the next. As Burke Harris observed in The Deepest Well, “For many families, it seemed that toxic stress was more consistently transmitted from parent to child than any genetic disease I had seen.”
Leveraging Her Superpowers
Burke Harris, 44, was born in Canada, the daughter of two Jamaican professionals. As a young child, she and her family moved to Silicon Valley, where her father was a professor of biochemistry at Stanford University and her mother a nurse. Burke Harris earned a medical degree from the University of California, Davis, and completed her pediatric residency at Stanford. After her MPH studies at the Harvard Chan School, she joined the California Pacific Medical Center, where she developed programs that aimed to end health disparities in San Francisco. Today, she and her husband—Arno Lockheart Harris, a clean-power entrepreneur—are raising four sons.
While Burke Harris’ immersion in the science of ACEs shaped her career, her acquaintance with family adversity began much earlier. As she shares in The Deepest Well, her mother suffered from untreated paranoid schizophrenia, and Burke Harris and her four brothers never knew whom they would encounter when they came home from school: “happy Mom or scary Mom.” Burke Harris’ older brother Louis also developed schizophrenia. When Burke Harris was 17, Louis opened the door of their mother’s car at a stoplight and walked away. She has not seen him since and doesn’t know if he is alive or dead.
How did Burke Harris overcome her own ACEs? One source of support, she says, was her nurturing father. “My dad being a biochemist, he and I shared a passion and a love of science. On top of that, my dad was a very strong buffering, caregiving force in my life—which, as we know now, is a relationship associated with improved health outcomes for individuals who have experienced ACEs.” Burke Harris also credits her Jamaican culture—which places a premium on helping family members in need, no matter how distantly related—for tempering the emotional ups and downs of her youth.
When such social supports are present, early adversity can be transmuted into positive skills. “Our ACEs are also the sources of our superpowers,” she says. Growing up with an emotionally unpredictable mother, for example, Burke Harris says she learned how to read nonverbal cues—an essential skill for a physician, especially one attuned to the ACE framework of care. “My own experience of ACEs also helped me gain greater insight into the ways that ACEs could be impacting my patients,” she adds. “Being able to recognize those heart-pounding moments, but then, as a doctor, being able to say, ‘Well, what causes that heart pounding? Release of adrenaline. And what is the long-term impact of adrenaline on the body?’”
From Science to Action
Public health revolutions spring from both social movements and newly uncovered scientific facts. Sanitary reform in the 19th century emerged out of concerns about urban crowding and other harmful effects of the Industrial Revolution and was boosted by the discovery of microbes and the subsequent germ theory of disease. Cigarette smoking was a fashionable norm in the United States until the 1964 U.S. Surgeon General’s report linked the habit to lung cancer and heart disease, and a slew of subsequent research augmented the list of harms, giving rise to broad-scale tobacco-control efforts.
Today, the scientific evidence around ACEs is steadily growing. In the two decades since the original ACE study came out, 39 states and the District of Columbia have collected ACE data. Collectively, these studies have found that between 55 and 62 percent of the population have reported at least one adverse childhood experience, and between 13 and 17 percent have an ACE score of four or more. In November 2019, the CDC published a surveillance study of 25 states, conducted between 2015 and 2017, finding that 15.6 percent of adults reported four or more types of adverse childhood experiences. If these ACEs could have been prevented, the agency found, 1.7 percent of cases of overweight or obesity, 23.9 percent of cases of heavy drinking, and 44.1 percent of cases of depression could have been averted. Meanwhile, according to the Center for Youth Wellness, an estimated 35 million children in the U.S. currently suffer from toxic stress.
Burke Harris will bring this evidence to bear on clinical practice in California. The Newsom administration is investing more than $100 million to reimburse health care providers for ACE screening and to train providers. Beginning in January 2020, all Medicaid enrollees in California of all ages will receive ACE screening and, where necessary, follow-up interventions. When ACE scores are high, physicians will connect patients or families to educational resources, social workers, or mental health care. Patients will also be tracked prospectively to help researchers determine which interventions work best. Indeed, California will be the first state in the country to reimburse Medicaid providers at this scale for ACE screening in both children and adults.
“The part that’s fun for me is looking at the evidentiary base for what improves outcomes,” says Burke Harris. “The strength of the evidence linking ACEs to health isn’t the same as the evidence behind risk factors for heart disease or diabetes. Much, much more research needs to be done. But in addition to implementing the interventions for which we do have strong evidence, we have the opportunity to build the field—to advance clinical care for adverse childhood experiences and their health consequences.”
In California, the public health community is rooting for her. “I’m a huge fan of Nadine’s leadership and grit and resolve. She’s not only a brilliant speaker and advocate on this issue, but she’s got a ton of moxie,” says Robert K. Ross, president and CEO of The California Endowment, a private, statewide foundation dedicated to expanding access to quality health care. “As physicians, we’re trained in the art of one-on-one patient engagement. Nadine has this knack for engaging a room of a thousand people in a way that makes you feel like you’re having a one-on-one conversation with her.”
But Burke Harris’ ambitious agenda won’t be easy to put in place, Ross adds. “It’s going to be a substantial lift. Health delivery systems don’t do a very good job on prevention to begin with. The childhood trauma and adversity issue really goes upstream—about as upstream as the health delivery system could possibly go. Questions about how to screen and assess and follow up patients, how to finance these services within current funding streams: All of that remains to be worked out.” Adds Kiran Savage-Sangwan, executive director of the California Pan-Ethnic Health Network, “It is important that the screening be implemented in a way that is culturally responsive and does not lead to further stigmatization of low-income Californians or people of color. This is a real concern and will need to be carefully considered in order for the screening to have the desired impact.”
Despite these obstacles, Ross is convinced that Burke Harris will succeed. “She’s going to embed the matter of childhood trauma in the discourse of health reform in California. It won’t be a one-off, nice-to-have option, or an intriguing, curious tidbit. It will be core to what health reform needs to be about for our state—and, hopefully, will set a tone for the nation.”
In 2020, Burke Harris will issue a major report on ACEs and toxic stress, detailing statewide prevalence, health impacts, and treatment strategies in California. “The report will be a road map for a public health response,” she says.
Burke Harris hopes to see more research on the biomarkers of early adversity, partly because such signals would improve scientists’ ability to measure the toxic stress response and gauge the effectiveness of interventions. Proven biomarkers could also help doctors intervene early, when patients are most apt to respond to treatment. “The more proximally we can measure these biological impacts,” Burke Harris says, “the more precise we can be in understanding whether or not our interventions are effective.”
Trauma-Informed Health Care
Ultimately, she wants all primary care—for both children and adults—to be “trauma-informed care.” “One basic of trauma-informed care is having the entire clinical team trained to support patient safety, confidentiality, and privacy, in order to avoid triggering or retraumatizing patients. Another basic is supporting and connecting patients and families to resources. And another is understanding the principles of self-care,” she says. Ideally, every pediatric or primary-care practice would be integrated with mental health services available in the same office.
One such model of enlightened medical care comes from the site of Burke Harris’ career-shaping work: the Center for Youth Wellness. Providers screen all kids for ACEs—with a questionnaire that takes less than three minutes to fill out—and conduct regular physicals. For children under 12, the child’s caregiver fills out the screening questionnaire. For those 12 and over, both the patients and the caregivers separately complete the forms.
Burke Harris and her colleagues have found that when the ACE screening tool is “deidentified”—that is, when respondents are asked simply to tally the total number of ACEs rather than specifically identify each one—people are more apt to disclose their experiences. But both identified and deidentified versions of the screening tool are available, depending on the preference of the physician.
At the center, children with ACE scores of four or more receive multidisciplinary treatment, including mental health counseling, mindfulness instruction, home visits, nutrition counseling, and other services—“a top-to-tail health care home for kids,” as Burke Harris puts it. The young patients are taught how to weave into their lives six proven, stress-reducing activities: getting enough sleep, regularly exercising, eating a healthy diet, learning mindfulness skills, monitoring their mental health and getting help when needed, and seeking out healthy relationships with adults. Studies show that these interventions work because they target the underlying biological mechanisms of toxic stress: a dysregulated stress-response system and the neurologic, endocrine, and immune disruptions that follow. In some cases, children also receive psychotherapy with their parents or caregivers. And mental health and wellness services are offered to parents, to break the unhealthy emotional patterns within families.
Burke Harris is convinced that the earlier health care providers treat toxic stress, the less expensive, less intensive, and more effective medical care will be over the long haul. As she told an audience during an April 2019 listening tour of California, “Adversity is not destiny. The science is clear: Early intervention improves outcomes.”
In The Deepest Well, Burke Harris describes the wide ripple effects of childhood adversity: “Toxic stress affects how we learn, how we parent, how we react at home and at work, and what we create in our communities. It affects our children, our earning potential, and the very ideas we have about what we’re capable of. What starts out in the wiring of one brain cell to another ultimately affects all of the cells of our society, from our families to our schools to our workplaces to our jails.”
Some critics have argued that the ACE paradigm medicalizes inequities perpetuated by the structure of our society. And while the standard ACE questionnaire has 10 items, some practitioners would like to see that list expanded to include racism, poverty, homelessness, and other damaging social determinants of health. Burke Harris disagrees—at least for now. The original ACE criteria, she says, are supported by robust data linking specific exposures with specific diseases, such as cardiovascular disease or depression. “We know that racism, poverty, and homelessness are risk factors for toxic stress,” she says, “but we need to do the specific analysis to assess the independent contribution of these factors to rates of chronic diseases, such as cardiovascular disease.” As she sees it, when the science behind the biological impacts of ACEs is refined and validated, it could then be usefully deployed to assess the effects of broader social determinants of health.
The Revelatory Power of ACEs
Above all, Burke Harris wants to see more open discussion around early adversity and its lifelong consequences. “The fact that two-thirds of Americans have experienced ACEs means that two-thirds of Americans recognize what this looks and feels like—in a really personal way. It also means that there’s probably not one American who is not impacted by ACEs, either themselves or through someone they love, a family member, a co-worker, someone whom they care deeply about. And when people understand that this is about basic biology, and that what happened to you can impact your risk for later-life health consequences, that makes finding solutions a shared priority. That is what it’s going to take for us to create true breakthroughs.”
She acknowledges that facing up to ACEs, whether individually or as a society, isn’t easy. As she writes in The Deepest Well, “ACEs and toxic stress thrive on secrecy and shame, both at the individual level and at the societal level. We can’t treat what we refuse to see. By screening for ACEs, doctors are acknowledging that they exist. By being open about ACEs with friends and family, people are normalizing adversity as a part of the human story and toxic stress as a part of our biology that we can do something about.”
Indeed, she says, we know enough to act right now. “The piece that’s the most wrenching for me is the data about how we can improve health with buffering care, and the fact that so few people seem to know this data,” Burke Harris says. The buffering effects of a relationship with a safe, stable, nurturing adult help children regulate their biological stress response, so that it functions normally. “One study showed that when individuals with four or more ACEs had the full range of buffering assets—including a trusted adult whom they felt like they could say anything to or connect with—their self-reported childhood poor health, which included things like headache and abdominal pain and other pediatric diseases, dropped from 59.8 percent to 21.3 percent. It was a dramatic difference, and yet this information is not widely known or widely applied. That, for me, is the heartbreak.”
When Burke Harris makes public appearances, strangers often come up to her and share their ACE scores. Their openness affirms Burke Harris’ contention that grappling with the issue of toxic stress should not be confined to the realm of science but must become a national movement, a kind of public consciousness-raising.
“For a lot of people, it’s a validation of their lived experience. And oftentimes, when people share with me their ACE scores, they also share with me either some of the health consequences they’ve experienced or the buffering factors in their lives that they feel have made a difference for them,” Burke Harris says. “Learning about ACEs is revelatory. It affects the lens through which we see the world.”
Madeline Drexler is editor of Harvard Public Health.
Portrait by Christie Hemm Klok for Harvard Chan.