One More Unhealthy Legacy of Racism

America has a weight problem.

But the nation’s expanding girth, with its associated risks of diabetes and cardiovascular disease, isn’t evenly distributed: the battle of the bulge is hitting African-American women particularly hard. According to one study, between 1999 and 2002, 77 percent of black women were overweight or obese compared to 57 percent of white women.

Now research out of Boston University’s Slone Epidemiology Center suggests that racism — or at least perceived racism — may account for some of this disparity. The study, led by Yvette Cozier, a School of Public Health assistant professor of epidemiology, appeared in the June 2009 Annals of Epidemiology. It was based on data gathered by the ongoing Black Women’s Health Study, administered by the Slone Center and Howard University.

In a 1997 questionnaire, about 43,000 participants were asked to rate their perceived experiences of racial discrimination. Women were asked to rate the frequency of experiences such as receiving poorer service in restaurants and stores or being treated as dishonest or less intelligent or threatening. Their answers to perceived “everyday racism” could range from “never” to “almost every day.”

Data on “lifetime racism” was gathered with yes or no questions asking if the women ever felt “treated unfairly due to your race” on the job, in housing, or by the police.

About 34 percent reported at least one incident of everyday racism per month, and 80 percent said they’d experienced some form of job, housing, or police discrimination based on race.

“These were certainly high rates of exposure,” says Cozier. “But they weren’t entirely surprising.”

The researchers then tracked the women’s weight change over eight years with follow-up questionnaires every two years (and a sampling of physical examinations to confirm the data). On average, participants gained a little more than 11 pounds. But women reporting the most everyday racism gained about a pound more than women perceiving the least discrimination. A similar difference in weight gain emerged between women who said they’d experienced discrimination on the job, in housing, or by police versus women who said they had not.

The weight gain difference emerged even when researchers controlled for other variables, such as income, body size, and education; about 97 percent of the study participants were high school graduates and 44 percent had college degrees. “This shows that even among educated black women, there are still effects of racism and uneven treatment, which results in uneven health,” Cozier says.

She and fellow researchers hypothesize that stress related to perceived racism causes elevated hormone levels in the central nervous system; an increase in cortisol secretion activates lipoprotein lipase, which increases fat retention. Much of the evidence for this link is from animal studies. Blood work was not a part of the study. “This was observational research,” says Cozier. “Hormone studies need to be properly timed to coincide with exposure to the stressor.”

Cozier believes the findings fit a pattern of health disparities that lead black women to be at greater risk than white women of developing other diseases, including cancer and heart disease. Two years ago, for instance, she found an apparent link between comparatively high levels of hypertension (high blood pressure) in black women and the fact that these women tend to live in poorer neighborhoods than white women of the same education and income.

If nothing else, says Cozier, she hopes that the latest research will help people acknowledge that “there are multiple sources of stress, that racism is one of them, and that it has physiological effects.”

Chris Berdik can be reached at cberdik@bu.edu.

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