When his flight touched down in Charlotte, North Carolina, in 2022, Clint Smith was aware of the restlessness among his fellow passengers. Charlotte is a major travel hub, so many people had connecting flights they were anxious to catch. As soon as the fasten seatbelt sign switched off, several people stood up and began jostling to retrieve their bags from the overhead compartments before attempting to squeeze through the aisle to the front of the plane to disembark. Amid the jostling, one interaction began to attract attention. Two passengers, a Black woman and a White woman, both middle-aged, had bumped into each other during the rush and started arguing. Clint was standing close by. As they got off the plane, the White woman turned to the Black woman and—red with anger—called her the N-word. Clint locked eyes with the Black woman, as the White woman disappeared off into the crowded airport terminal.
Clint happens to be a poet and an author, who has written extensively about Black history, racism, and slavery in the US. He decided to write about how the altercation at the airport had affected him, as a Black man. He posted about it on social media, expanding on the experience in an article for The Atlantic a few weeks after the incident.125
We can only imagine how that Black woman must have felt in that moment and how the experience affected her. But what struck me about Clint’s account was the extent to which the incident had also affected him, both mentally and physically, even though he hadn’t been the direct target of the racist abuse. “It was as if my skin was struck by a match and fire spread through my entire body. My heart’s once metronomic tempo accelerated into a gallop, my blood pumping as if it was trying to tell me to run away,” he observed in the Atlantic. Clint noticed that for hours afterward, he felt the impact of the White woman’s words in his body. “I couldn’t shake it,” he wrote. “Although the venom of her voice had not been oriented directly at me, I experienced the debris of her language. I felt it, quite literally, in and under my skin.”
In addition to the systemic forms of racism that we explored in the previous chapter, interpersonal racism—in Clint’s words, “intimate, direct, one-on-one racism”—can also affect a person’s body and mind.
Experiencing racism in all its forms is exhausting, and as Clint astutely observed in his article, you don’t have to be the target of an individual racist act to experience its harmful impact. There is burgeoning evidence that experiencing racism—or even just the anticipation of experiencing racism—harms people’s health over time. Public health researcher Arline Geronimus first started thinking about this when she was a student at Princeton University in the late 1970s. Alongside her studies, she worked part-time at a school for pregnant teenagers in Trenton, New Jersey. Geronimus noticed that the teenagers were experiencing chronic health conditions that her wealthier, largely White Princeton classmates rarely did. She started to wonder whether there was a connection between the chronic health problems that these teenagers were experiencing and the stresses of their environment. Later, as a graduate student, Geronimus began her research by trying to address a question that we touched on in the first chapter of this book: Why do Black women in the US experience worse childbirth outcomes on average compared with White women?
During this time, in the 1980s and early 1990s, there was widespread recognition that the twenties through early thirties constituted prime childbearing ages, with lower risks associated with childbirth compared to younger or older women. Geronimus observed that this wasn’t a universal truth. “In particular for Black Americans the risk of poor birth outcomes increased with age from the mid-teens just straight on up, so that ages we sort of assumed were perfectly healthy childbearing ages were already higher risk for Black moms,” Geronimus explained during an April 2020 interview on an episode of WNYC podcast The United States of Anxiety. “It led me to wonder,” Geronimus continued. “Is there something happening in the lives of Black women that leads them to poor health earlier than White women?”126
As a possible explanation for the disparity, Geronimus proposed the “weathering” hypothesis in a highly influential paper published in 1992, by which point she was working as an assistant professor at the University of Michigan. It was a radical idea at the time—she proposed that the mental and physical stress caused by experiencing racism day in and day out could be damaging Black people’s health directly, resulting in increased vulnerability to disease and death. “Because of the multiple chronic and often toxic stressors across your life course, you would experience a stress mediated wear and tear on your organs and body systems and cells that in effect leaves you more vulnerable to poor health—it causes a kind of accelerated biological aging and premature death,” she said. “I called it weathering because of the two different meanings that that word has. You can talk about weathering as being exposed to things that erode you, like ‘the rock was weathered by the storm,’ and you can also talk about weathering as in coming through a storm, as in ‘the business weathered the recession.’ ”127
As scientific understanding in the fields of stress physiology and epigenetics grew over the next two decades, evidence for the weathering hypothesis began to mount, improving our understanding of how racism impacts physical and mental health. Researchers are increasingly discovering how the health effects of chronic exposure to discrimination within societies could help explain racial and ethnic disparities in health and disease outcomes that aren’t accounted for by other factors. Living in a racist society can harm the health of all Black people, even those who don’t directly experience racism, according to Delan Devakumar, a public health researcher at University College London. “This is akin to other environmental risk factors for health, such as high levels of air pollution,” Devakumar told the Economist in a 2020 interview. Early evidence for this phenomenon began to emerge in the 1990s. At the time, separate, parallel research was beginning to reveal the impact that the stress of experiencing racism has on the body.128
Several studies conducted in the 1990s and early 2000s demonstrated that exposure to racist provocation in a laboratory setting was associated with increases in heart rate and blood pressure levels among African American people. But racism isn’t a one-off experience in a lab—and neither is the stress associated with it. The physiological consequences of chronic exposure to stress—including heightened levels of stress hormones like adrenaline and cortisol, as well as increased blood pressure—were well established by this point. The term “allostatic load” had been coined to describe the cumulative wear and tear that chronic exposure to stress responses has on the body over time. Allostatic load-scoring was established as a way of quantifying these physiological effects by combining measures of blood pressure and levels of stress-related biomarkers in the blood. Research by Geronimus and others in the US showed that Black people had higher allostatic load scores on average compared to White people, even after adjusting for other sociodemographic characteristics. Then, in 2010, another study led by Geronimus hinted that Black people might be experiencing accelerated biological aging compared to White people, as a product of greater allostatic load.129
A year earlier, the 2009 Nobel Prize in Physiology or Medicine had been awarded for the discovery of how chromosomes are protected by telomeres—caps of repetitive DNA at their ends, which shorten each time a cell divides. Telomere length can therefore provide an indicator of how young or old a person is at the cellular level. In their study, Geronimus and her team found that Black women between the ages of forty-nine and fifty-five had shorter telomeres compared to White women of the same age, equating to an estimated cellular or biological age gap of almost eight years.
Research by Geronimus and others caught the attention of David Williams, a social scientist and public health researcher at Harvard University’s School of Public Health. Williams was shocked by the gaps in health and life expectancy between Black and White people in the US. In a widely cited 2012 paper, he highlighted the fact that Black people had an overall death rate that was 30 percent higher than that among White people in 2007, and that Black people had higher death rates than White people for 10 of the 15 leading causes of death at the time, including for heart disease, cancer, and stroke.130
This Black-White life expectancy gap still exists. As of 2017, the average life expectancy at birth for a non-Hispanic White person in the US was 78.5 years, compared to 74.9 years for a non-Hispanic Black person. This gap is predicted to widen because of the disproportionate impact of Covid-19 on Black populations. As a public health researcher, Williams was interested in further investigating the contribution of racism to health disparities, but he felt that a method for measuring racism directly was lacking. “We measure self-esteem,” he said in his now famous 2016 TED talk. “There’s no reason we can’t measure racism if we put our minds to it.” Williams devised the Everyday Discrimination Scale to capture, as he has described it, “ways in which the dignity and respect of people who society does not value is chipped away on a daily basis.” The scale has become one of the most widely used measures to assess perceived discrimination in health research. And work by Williams and others has since demonstrated that high levels of perceived discrimination among racial and ethnic minority groups are associated with an elevated risk of a broad range of illnesses, from cardiovascular disease to breast cancer to mental health conditions.131
Even just the anticipation of experiencing racism may be harmful to health. Shawn Utsey, a psychologist at Virginia Commonwealth University and an expert on racism-related stress, explained this concept to me. Stress isn’t only caused by overt experiences of racism, Utsey said. Often it is caused by the broader challenges associated with negotiating a racist society, he said.132
“Black folks don’t necessarily have to experience racism to be stressed by racism. Just the anticipation that you will experience racism is stressful,” Utsey explained. He gave me an example, drawn from his own lived experience as a Black man in Virginia. “If I’m about to take my family shopping at the mall in the White part of town, which is probably what we would do, because they would be better resourced,” he began, “almost immediately, when planning that trip, I would have to factor in the possibility that we would be treated poorly because of our race.” Utsey went on, “And I would experience stress, even before anything ever happened.” However, he acknowledged, “it may never happen.” “But the possibility—the reality of the physiological nature of stress will still visit me, because of that cognitive process that tells my body that I’m about to experience fight or flight,” he said.
Listening to Utsey, I started to reflect on some of my own everyday experiences, which up to this point I had thought to be quite trivial and mundane—things like being followed around shops by security, having my hair touched by people without asking or being racially profiled at airports. I also thought back to less frequent but perhaps more acutely stressful occurrences, like having the N-word shouted at me during a night out in my hometown in the Netherlands or being told I didn’t “look British” by German airport police after losing my passport as a teenager. I had long understood individual incidents like these—sometimes euphemistically referred to as microaggressions—to be inconvenient and unpleasant but, until my conversation with Utsey, I hadn’t really reckoned with the fact that they may collectively be harming my health.
“Racism is beyond an event,” Utsey explained to me. “It’s not just an event that happens to you. It’s a physiological process that taxes your autonomic [nervous] system and causes physical illness. And this is really at the crux of health disparities,” he argued. “Everyone’s talking about, why are Black folks less healthy in a number of realms? Is it access to health care? Probably. Is it poverty that exposes them to more stress, poor diet, poor nutrition? Yeah. But I think the chronicity of race-related stress that creates this prolonged activation is also problematic,” he said.
Utsey first began examining this issue from an academic perspective as a graduate student in New York in the 1990s. He was working as a counselor in Harlem at the time and noticed that the items on the Holmes-Rahe Life Stress Inventory—then a widely used scale among counselors to assess life stress—didn’t reflect the lived experiences of his clients, many of whom were Black. “There was no reference to racism or police brutality,” he told me. So, Utsey created his own scale to measure life stress among Black populations. He included examples of everyday racism that might induce stress like “You have been followed by security (or employees) while shopping in some stores” and “You called the police for assistance and when they arrived they treated you like a criminal.” Since he published his scale, called the Index of Race-Related Stress or IRRS, in 1996, multiple studies by Utsey and others have linked chronic exposure to racism-related stress with reduced mental and physical well-being among Black people and people belonging to other marginalized racial and ethnic groups in the US and elsewhere.133
Over a lifetime, racism-related stresses and challenges may take a serious toll on both body and mind. In 2019, a team that included health disparities researcher Michele Evans at the National Institutes of Health found potential signs of this in the brains of a group of older African American people. Evans and her colleagues were investigating why Alzheimer’s-related dementia is more prevalent among Black people compared to White people in the US and whether this might be linked to racism. Over a five-year period, she and her team surveyed a group of seventy-one African American study participants about their experiences of racism. They also used magnetic resonance imaging (MRI) to scan the participants’ brains and measure something called white matter lesion volume—an early indicator of cognitive decline. They found that among older African Americans, increases in perceived lifetime discrimination burden were associated with increases in white matter lesion volume over the study period. Separate research has linked perceived frequent experiences of racism among African American women with self-observed declines in cognition.134
In other words, race may be a social rather than a biological construct, but racism clearly affects our biology.
In addition to the potential harm caused by the chronic humdrum of day-to-day discrimination, more acute and traumatic experiences of racism may also cause lasting damage to the brain. Emerging evidence points toward a link between past experiences of trauma and dementia risk in later life.
Research suggests that US veterans with post-traumatic stress disorder (PTSD) experience higher rates of dementia than those without PTSD, for instance. A study of first responders involved in search, rescue, and recovery during the 9/11 attacks on the World Trade Center in New York also found that those with PTSD experienced increased cognitive impairment and possible dementia compared to those without the condition. As of 2023, the American Psychiatric Association defines PTSD as “a psychiatric disorder that can occur in people who have experienced or witnessed a traumatic event, series of events or set of circumstances [such as] natural disasters, serious accidents, terrorist acts, war/combat, rape/sexual assault, historical trauma, intimate partner violence and bullying,” and, although its website notes that people belonging to racial and ethnic minority groups—particularly “Latinos, African Americans, and Native Americans/Alaska Natives”—are “disproportionately affected and have higher rates of PTSD than non-Latino Whites,” the definition of and criteria for PTSD have been criticized by some psychiatrists and psychologists in the past for their lack of attention to stressful events connected to racial discrimination and experiences of racism.135
Race-based traumatic stress—defined by psychiatrist Robert Carter in a seminal 2007 paper as “emotional trauma brought on by the stress of racism”—has been found to share some symptoms with PTSD, while racism-related stress more broadly has been associated with more severe PTSD outcomes. A more recent analysis that examined the existing scientific literature on racial discrimination and trauma in the US confirmed that there was a positive association between the two and called for more research in this area.136
But we don’t need to look to scientific studies to understand the deep-seated and long-standing relationship between racism and trauma. A year after witnessing and capturing on camera the murder of George Floyd, by White police officer Derek Chauvin, in Minneapolis in May 2020, when she was just seventeen years old, Darnella Frazier wrote a social media post about the trauma the experience had caused her. “I am 18 now and I still hold the weight and trauma of what I witnessed a year ago,” she wrote. “It’s a little easier now, but I’m not who I used to be. A part of my childhood was taken from me,” said Darnella. “My 9-year-old cousin who witnessed the same thing I did got a part of her childhood taken from her,” she added.137
What started out as a normal day for Darnella, who had been walking her young cousin to the corner store, quickly turned into a nightmare when she came across George Floyd being arrested. She told a court in 2021 that she had started recording the incident on her phone, because she “saw a man terrified, begging for his life.” We all know what happened next.138
I remember watching Darnella’s video on my smartphone from my living-room-turned-office in Berlin and feeling sick. I felt even worse when I learned that the video had been filmed by a seventeen-year-old. Even watching a video like that can be extremely traumatic, let alone witnessing what happened firsthand and capturing it for the world to see. A survey of 134 mainly Black or Latinx college students in the US published less than two months after George Floyd was murdered found that the students, aged between 18 and 24, reported experiencing symptoms consistent with PTSD after viewing videos on social media showing Black men being killed at the hands of police officers.139
“Everyone talks about the girl who recorded George Floyd’s death, but to actually be her is a different story,” Darnella wrote in her social media post. “Although this wasn’t the first time, I’ve seen a black man get killed at the hands of the police, this is the first time I witnessed it happen in front of me. Right in front of my eyes, a few feet away,” she said. “It changed me. It changed how I viewed life. It made me realize how dangerous it is to be Black in America.”
Several studies have suggested that experiencing trauma during childhood is associated with dementia risk later in life. In 2017, a team of researchers led by Kylie Radford at the University of New South Wales in Australia identified an association between childhood trauma and late-life dementia risk among Aboriginal and/or Torres Strait Islander peoples. Although the word “racism” isn’t mentioned in their paper, Radford and colleagues mention that the study participants’ scores in a childhood trauma questionnaire were associated with several indicators, including separation from family “by a mission, the government or welfare.” Many First Nations children were forcibly removed from their families between 1910 and the 1970s, as part of a series of assimilation policies implemented by the Australian government based on racist and pseudoscientific notions of Black inferiority and White superiority. They proposed that First Nations children should be either allowed to “die out” or forced to assimilate into White communities. Mixed children, of First Nations and White parentage, were especially vulnerable to being separated from their families as it was thought that their perceived lighter skin color would make it easier for them to blend into White communities. The generations of children removed under these policies became known as the Stolen Generations, and the resulting legacy of trauma and loss continues to affect First Nations communities to this day—including participants in Radford’s study—the results of which may at least partly explain why Aboriginal and/or Torres Strait Islander peoples experience a rate of dementia three to five times greater than Australia’s wider population.140
Sleep disorders such as insomnia are also common following traumatic experiences. In her social media post on the one-year anniversary of George Floyd’s death, Darnella explained how the trauma from witnessing his murder had impacted her sleep. She described “closing my eyes at night only to see a man who is brown like me, lifeless on the ground,” recalling that she “couldn’t sleep properly for weeks” afterward. “I used to shake so bad at night my mom had to rock me to sleep,” she said.141
Sleep is a biological necessity. “If you’re not getting a healthy amount, all sorts of things go wrong,” sleep researcher Girardin Jean-Louis at the University of Miami in Florida told me. Failing to get between seven and eight hours of sleep a night has been associated with elevated risks of obesity, high blood pressure, diabetes, cardiovascular disease, and cancer, explained Jean-Louis. Yet sleep is a privilege. According to Jean-Louis, in the US, “Blacks as a whole group are sleeping 30 minutes less, 40 minutes less, compared with Whites.” Indeed, a 2017 study that analyzed the sleep habits of 426 people from across the country found that Black people slept 40 minutes less than White people on average. It additionally found that Black people experienced poorer sleep quality than White people, spending 10 percent less time asleep while in bed, and that the lower amount of sleep and quality of sleep among Black people was associated with increased risks of cardiovascular disease and diabetes. Research by Jean-Louis and his colleagues, both in the US and the Netherlands, has also identified racial and ethnic inequalities in sleep health.142
Jean-Louis said that he spends a lot of time visiting churches, barbershops, and beauty salons—places at the heart of many Black communities throughout the US—to share his knowledge on the importance of sleep for health. His conversations with the people he meets there hint at some of the factors that may underlie the racial sleep gap.
“At the barbershop you will hear some people say, ‘Well, gee, you know, each time I hear a siren behind me as a driver, I tense up, my blood pressure goes up.’ Well, after a while, through conditioning, even if you’re not driving—you may be at home—if you hear a police car [siren] going or if you see flashing lights going by, through conditioning, you may come to associate those things with something that causes high blood pressure,” he said, noting that Black people are more likely than White people to be stopped by police while driving in the US. Such anxiety is unlikely to be helpful if you are trying to fall asleep.
Jean-Louis suspects that the higher levels of noise, light, and air pollution known to be present in areas where Black people and other people of color disproportionately reside may also be a contributing factor to sleep disparities in the US. Further, Black and Latino people are additionally overrepresented among workers who do night shifts, which is associated with poorer sleep health due to disruption of the body’s internal clock or circadian rhythm and has been classified as “probably carcinogenic” by the WHO.143
Jean-Louis additionally touched on something else that, as a descendant of transatlantic slavery, I found particularly intriguing. “How does trauma associated with slavery contribute to poor sleep?” he mused. “We don’t know. This is sort of the question we are trying to answer in our own lab,” he said. “If slavery is in fact a traumatic event, much like any other traumatic event, it has long-lasting effects on folks, even generations after,” he said. His work exploring possible health effects of trauma associated with the history of transatlantic slavery was at a very early stage when I spoke to him, but the question of whether and how the effects of trauma might be transmitted intergenerationally from parents to their children—and even to subsequent generations—has long stoked both scientific and general interest. And it has been explored scientifically in the context of another historical, racism-fueled atrocity.
Several studies have found evidence of a greater prevalence of PTSD among the adult children of Holocaust survivors in comparison with other adults, particularly among those whose parents also experienced Holocaust-related PTSD. Initially, this pattern was mainly attributed to the cultural transmission of trauma, for example through parental behavior or storytelling. But as our understanding of genetic inheritance improved around the turn of the century, another possible explanation emerged. Namely, that trauma could cause changes to our biology, which might then be transmitted to our offspring. “More and more, we are seeing that trauma can in fact change the genetic makeup,” Jean-Louis told me. “Epigenetics plays a role in some of our health, and we’re learning more and more about this,” he explained.144
Epigenetics is the study of changes to DNA that don’t affect the underlying DNA sequence but which can influence how our genes work, for instance, by determining whether or to what extent a particular gene is switched on or off. These epigenetic changes are chemical tags or marks, which are added to or removed from the DNA in response to environmental triggers. In the 2000s and 2010s there was a huge amount of scientific and general excitement about the possibility of transgenerational epigenetic inheritance—the idea that epigenetic changes could be passed on to subsequent generations. In other words, that environmentally induced changes to our DNA might be heritable. Several studies demonstrated the phenomenon in animals, such as mice, while others provided indicators that it might happen in humans too.145
During the same time period, it was becoming clear that specific patterns of epigenetic changes are associated with certain health conditions, including psychiatric conditions such as PTSD. As this emerging scientific field exploded, some researchers began to wonder whether epigenetic inheritance might therefore help to explain observations of apparent intergenerational transmission of the effects of trauma. Rachel Yehuda, a psychiatry and neuroscience researcher at Mount Sinai School of Medicine in New York, was one of them. She set up a clinic for Holocaust survivors in the 1990s and was among those who first noticed and published findings on the pattern of increased rates of PTSD in their children.146
Fast-forward a couple of decades to the epigenetics era, and Yehuda and her colleagues had made another intriguing discovery. In a small study they found, to great general interest, that epigenetic changes associated with trauma were present on the same stretch of DNA in both Holocaust survivors and their children. The stretch of DNA in question sits within a gene called FKBP5, which is involved in the body’s response to stress. In their paper, Yehuda and her team concluded that their findings provided “a potential insight into how severe psychological trauma can have intergenerational effects” and speculated that these effects might have been mediated by changes to the parental egg or sperm cells that formed the offspring. But they acknowledged that this couldn’t be definitively determined based on their results, since they didn’t directly analyze DNA from sperm or egg cells in their study, and they highlighted that it would be necessary for future studies to look at multiple generations in order to differentiate epigenetic versus socially mediated effects.147
In fact, teasing apart the effects of sociocultural factors versus any potential epigenetic mechanisms by which trauma might be transmitted down generations is increasingly proving to be, at best, extremely scientifically challenging and, at worst, impossible. For example, in addition to being affected by their parents’ trauma through altered parenting behavior and storytelling, the children of Holocaust survivors have undoubtedly also been affected simply by virtue of belonging to a marginalized group. After all, we have just seen several examples of how chronic exposure to racism—including antisemitism—can harm health. This becomes even more complex with subsequent generations, such as the grandchildren and great-grandchildren of Holocaust survivors or even the many generations of descendants of transatlantic slavery, whom Jean-Louis referred to earlier.
Academic and author Joy DeGruy used the term “Post Traumatic Slave Syndrome” in her 2005 book by the same name to encompass the complex and multiple ways in which slavery and continued discrimination against Black people manifest as intergenerational psychological trauma among Black Americans. “Ten years ago, people were like, ‘Oh my God, that’s ridiculous,’ ” said Dr. Alfiee, referring to DeGruy’s theory. “It’s only been recently that more people have come around to understand that what she’s talking about is, you had, what, four hundred years of Black people having no rights, being treated as subhuman, right? Denigrated, raped, murdered, all kinds of things,” Dr. Alfiee continued. “In that period of time, no one has ever provided any kind of universal mental health care for those of us who are descended from people who were enslaved,” she pointed out. “I think it has a direct impact [on health],” she said.148
That impact may not be mediated through epigenetic inheritance, but I don’t think that makes it any less real. I think that people experiencing trauma related to racism, including traumatic racist events in the past or present, deserve to feel validated and supported.
The effects of interpersonal racism on health are perhaps more challenging to record, measure, and quantify, compared to those of systemic racism, but that doesn’t mean they aren’t worth examining. These two broad categories of racism are complex and overlapping—as are their impacts on health. In fact, I would argue that it is almost impossible to understand the full impact of interpersonal racism without considering it in the wider context of systemic racism and societal inequality. This comes across in Clint’s telling of the racist incident he witnessed at the airport in Charlotte, North Carolina.
Clint had locked eyes with the Black woman as the White woman vanished into the crowd in the terminal, her racist language still hanging in the air. “I think we were both processing what had just occurred, how quick this woman had been to wield that word as the weapon she knew it was, and how quickly she had then run away,” he recalled in his 2022 Atlantic article. Afterward, he and the Black woman who had been the target of the racist abuse reported what had happened to a staff member, but by then the White woman had already disappeared. With the benefit of hindsight, Clint wondered whether he should have done anything differently. “Should I have responded faster? Should I have confronted the woman? Should I have stood in front of her to block her way until an airport official came over? But what would I have been hoping to achieve in that? For her to miss her flight? For her to be placed on a list? For her to apologize?” he asked. “Then I imagine the optics of a Black man attempting to physically prevent a smaller white woman from leaving, and immediately recognize the way that such a move would create its own spectacle, its own dangers,” he added.
What this demonstrates is that Clint and the Black woman standing beside him didn’t experience the racist incident at the airport in isolation, they experienced it within the wider context of a society in which there are significant power dynamics based on race. Those power dynamics, when combined with the daily microaggressions and acute instances of racism or racial trauma we have just explored, produce a perfect recipe for poor health among people belonging to marginalized racial and ethnic groups.
Of course, systemic and interpersonal forms of racism within societies overlap to harm health. A clear example of this is colorism—a form of racism where people within a particular racial or ethnic group are discriminated against based on skin tone or other racialized features, such as hair texture. And that’s where my investigation took me next.