Discrimination may accelerate the biological processes of aging, according to a new study led by researchers at New York University's School of Global Public Health.
Research links interpersonal discrimination to changes at the molecular level, revealing a potential root cause of differences in age-related disease and mortality.
"Experiences of discrimination appear to accelerate the aging process, which may contribute to disease and premature mortality, exacerbating health disparities," said Adolfo Cuevas, assistant professor of social and behavioral sciences at New York City's School of Global Public Health. University and senior author of a study published in the journal of Brain, Behavior, and Immunity-Health.
Research shows that people who experience discrimination based on their identity (such as race, gender, weight or disability) have an increased risk of a variety of health problems, including heart disease, high blood pressure and depression. Although the exact biological factors causing these poor health outcomes are not fully understood, chronic activation of the body's stress response is likely one contributor. Moreover, a growing body of research links chronic exposure to discrimination to the biological processes of aging.
To better understand the link between discrimination and aging, Cuevas and colleagues examined three measures of DNA methylation, a marker that can be used to assess the biological effects of stress and the aging process. Blood samples and surveys were collected from nearly 2,000 U.S. Adults as part of the Midlife in the United States (MIDUS) study, a long-term study of health and well-being funded by the National Institute on Aging.
Participants were asked about their experiences with three forms of discrimination: everyday, major, and in the workplace. Everyday discrimination refers to subtle and minor acts of disrespect in everyday life, while major discrimination focuses on acute and intense instances of discrimination (such as physical threats from police officers). Discrimination in the workplace includes unfair practices, limited professional opportunities, and punishment based on identity.
Researchers found that discrimination was associated with accelerated biological aging, with people who reported more discrimination aging faster biologically than those who experienced less discrimination. Everyday and major discrimination were consistently associated with biological aging, while exposure to workplace discrimination was also associated with accelerated aging, but its impact was comparatively less severe.
Deeper analysis found that two health factors—smoking and body mass index—explained about half the association between discrimination and aging, suggesting that other stress responses to discrimination, such as elevated cortisol and poor sleep, contribute to accelerated aging.
"Although behavioral health factors partly explain these differences, it is likely that a number of processes influence the association of psychosocial stressors with biological aging," said Cuevas, who is also a core faculty member of the Center for Anti-Racism, Social Justice and Public Health at the School of Global Health. Of Public Health of New York University.
Additionally, the association between discrimination and accelerated biological aging varied by race. Black study participants reported more experiences of discrimination and tended to have an older biological age and faster biological aging. However, White participants who reported fewer experiences of discrimination were more susceptible to its effects when they experienced it, perhaps due to less frequent exposure and fewer coping strategies. (Data for other racial and ethnic groups were not available in the MIDUS study.)
These results highlight the importance of combating all forms of discrimination to support healthy aging and promote health equity.