Racism is a powerful enough force that it can wear down a man's body. Those are the findings, at once common-sense and groundbreaking, in a study led by University of Maryland epidemiologist David Chae which examines the relationship between white blood cell telomere lengths and experiences with racism.
The study, "Discrimination, Racial Bias, and Telomere Length in African-American Men," to be published in the February 2014 issue of the American Journal of Preventative Medicine, is the first of its kind to explicitly measure the role that racism-related factors play in the aging process.
It's in the Blood
Chae and his team gathered 95 black men between the ages of 30 and 50 in the San Francisco Bay Area in 2010, and measured black men's white blood cell telomere lengths. Telomeres are repetitive sequences of DNA that sit like the plastic protective caps at the ends of shoelaces. When white blood cells replicate, DNA sequences at the very ends get chewed away, and telomeres are there to be, as Chae explains, "the sacrificial lambs" to protect the more crucial DNA from being damaged. (Telomeres are the glowing white dots at the end of chromosomes, pictured below.)
Telomere length is associated with mortality and age-related diseases like dementia, heart disease and Alzheimer's--the shorter they are, the higher the risk, which is why they're seen as a good indicator of physiologic age. Studies have shown that telomeres are also sensitive to psychosocial stress, which can speed up their depletion. "You could have two 35-year-olds who are of course the same age chronologically, but at a cellular level they might be very different depending on what they've experienced in life," says Chae.
People start out with roughly 8,000 base pairs and they wear down at a rate of 50 to 100 every year. Among black men who had internalized strong anti-black biases, those who experienced high levels of racial discrimination had on average 140 fewer base pairs of telomeres than those who reported low levels of racial discrimination. The combination of high levels of external racial discrimination and internalized anti-black attitudes was a toxic mix.
Researchers found, on the other hand, that there was a slight positive relationship between experiences of discrimination and telomere length in black men who had strong pro-black biases. That is, a positive racial identity could act as a kind of psychological buffer against the ravages of racism.
Testing the Unconscious
To get results, researchers surveyed subjects and asked them to gauge their experience with being discriminated against in nine venues, including criminal justice, education, health care, work and housing. To measure unconscious attitudes, researchers separately used the Implicit Association Test. This test flashes images of black and white people in front of respondents, and measures how quickly respondents associate each face with positive and negative characteristics. The faster the response, the more deep-seated the association.
In the U.S., national studies have found that 70 percent of respondents have an implicit anti-black bias--and roughly half of African-Americans do. It's seen as a rough proxy for determining unconscious bias, and depending on the subject, internalized racism.
"Racism and racial discrimination is an assault on one's self-concept," Chae explains. "And it involves not only physical acts but also the internalization of an ideology that posits that some groups are better or worse than others." Scientists theorize that when a black person has strong anti-black attitudes, the racism they encounter in their daily life can feel deserved, and that cumulative psychological toll can impact telomere length.
But it's not helpful to think of internalized racism as simply an individualized symptom of structural racism, says Brian Smedley, director of the Health Policy Institute at the Joint Center for Political and Economic Studies. It's deeply embedded in the larger apparatus of racial inequity, and is its own layer of oppression. Think, for instance, of the classic, heartbreaking doll study originally conducted by Kenneth and Mamie Clark in 1939. Researchers put a white doll and black doll in front of black children and asked them to identify the dolls' race, and point to which was the nice one, and which was the mean one. Children as young as three years old identified the white doll as good, and the black doll as bad.
The Realness of Racism
"What our and others' research shows is that racism is not some abstract artificial concept, but is part of the lived and social experience of African Americans in today's society--and that it has real effects on the body," says Amani Nuru-Jeter, a professor at UC Berkeley's School of Public Health and co-author of the study. Researchers say their findings can help explain some of the well-known racial health disparities in the U.S. For example, according to the Center for Disease Control, blacks in the U.S. have a life expectancy four years shorter than the rest of the country, and have diabetes at double the rate of whites. Black men in particular have a life expectancy that's six years shorter than white men, and black men are 60 percent more likely than white men to be diagnosed with prostate cancer. What's more, says Nuru-Jeter, "racism is a particular form of stress reported by over 75 percent of African Americans," so the public health implications are huge.
What scientists have found is that racism influences people's physical health in all these indirect ways--affecting access to health care, decent work, housing, healthy food and safe places to exercise. And it can have more direct consequences, typically by creating more stress in people's lives. Think about what happens to your heart rate and blood pressure when someone treats you harshly or unfairly, cutting you off on the freeway or pushing you out of the way to get onto the subway. We have physiological reactions to stress. Now, imagine it's racism we're talking about--something that people can experience "on a routine, chronic, everyday basis," Chae says. "It wears out our biological systems because they are being continually engaged ... and it can lead to this accelerated physiological wear and tear." Studies have shown that blacks' telomere lengths burn off at faster rates than people in other racial groups.
So What Do We Do?
When it comes to the public health interventions, Chae says the clear implication is that society needs to address systemic discrimination. "There needs to be greater enforcement of anti-discrimination legislation," in areas like housing and employment he says. Furthermore, policies like stop-and-frisk, even those which are facially neutral, "can negatively impact health."
It might be tempting to prescribe black people who have anti-black biases some kind of racial identity bolstering treatment, but says Chae, telling people to address their internalized oppression "is not my first line of treatment because it puts the burden on those who are victimized." Racism may manifest itself on the individual level, but that doesn't make it the right place to focus.
"It's quite right that we should be concerned with individuals but we will not change the dynamic, that unconscious thumbprint of society, until we change the broader social structure in our systems and understandings of difference and how we value different groups," Smedley says. "Race and racism are not limited to internal, individual dynamics."