Is Body Mass Index Racist?

Given the problematic origins of BMI, used to measure obesity, here’s what sisters need to recognize during that doctor’s office weigh-in.

Published September 09, 2021

Chiara Ghigliazza

For decades health care professionals have used body mass index (BMI) to determine if a person is overweight or obese and to assess health risks. But in 2020, the Huff Post published an article declaring, “The BMI Is Racist and Useless.” And in February 2021, Good Housekeeping ran an article exploring “The Racist and Problematic Origin of the Body Mass Index.” Sisters' researchers found multiple scientific studies suggesting computational bias linked to body measurement.

So, is BMI really racist?

“BMI is just weight adjusted for height. That’s all it is,” says Diana Thomas, Ph.D., a professor of mathematics at West Point who’s published research on exercise and obesity. “BMI by itself is not racist. People are racist.”

BMI becomes problematic when it is used to make assumptions about a person’s health — and even their character — without considering other important factors. And this is particularly troublesome for Black women who have the highest rates of "obesity" and being “overweight” as defined by BMI.

Weight has long been linked with morality. In her book Fearing the Black Body: The Racial Origins of Fat Phobia, Sabrina Strings, Ph.D., an associate professor of sociology at UC Irvine, argues that weight stigma has been used to oppress both Black and white women.

“In the United States, fatness became stigmatized as both Black and sinful. And by the early twentieth century, slenderness was increasingly promoted in the popular media as the current embodiment for white Anglo-Saxon Protestant women,” Strings writes. “The fear of the imagined “fat Black woman” was created by racial and religious ideologies that have been used to both degrade Black women and discipline white women.”

The Origins of BMI

The formula we now call the Body Mass Index, which many doctors rely on to predict health outcomes, wasn’t created by a health expert. In the mid-19th century, a Belgian statistician named Lambert Adolphe Jacques Quetelet was on a mission to figure out what the “average man” looked like so he could create a model of so-called “perfection.” To come up with his model — called the Quetelet index— he studied Europeans. Fast-forward to 1972 when American health researcher Ancel Keys, Ph.D., coined the term “body mass index” in a paper titled "Indices of Relative Weight and Obesity." Using the Quetelet index, Keys studied 7,424 men and defined the body mass index as a straightforward way to measure body weight in relation to height. You can calculate your BMI by dividing your body weight in pounds by the square of your height in inches and multiplying the result by 703. Or you can use the CDC’s BMI calculator.

Eventually more health experts began to link body fat with certain health risks. In 1985, the National Institutes of Health (NIH) started using BMI to define obesity in the United States.

And by 1998 the categories in use today were set:

Below 18.5 is underweight

18.5 to 24.9 is normal

25 to 29.9 is overweight

30 and over is obese

Beyond BMI

People who are considered overweight or obese are at a greater risk for chronic diseases, such as heart disease, type 2 diabetes, stroke and even cancer, according to the National Institute of Diabetes and Digestive and Kidney Diseases. But this doesn’t mean doctors should use BMI alone to predict a patient’s health outcomes.

Dr. Sharon Allison-Ottey, M.D., a health strategist, physician, health educator and author with a focus on older adults, women and minority populations, is much more concerned with numbers other than BMI.

“What’s your blood pressure? What’s your waist measurement? Tell me your hemoglobin A1C [or blood sugar levels],” Allison-Ottey says.

Waist circumference is a factor many doctors consider in addition to weight, and in 2009 Louisiana State University researchers found that Black people tend to have less belly fat than whites, even at the same BMI.

If you do have type 2 diabetes, cardiovascular health problems or high blood pressure in tandem with an overweight or obese BMI, work with your doctor to get these conditions in check. And don’t let your doctor simply “pat you on the head and say lose the weight through diet and exercise,” Thomas said. “If that worked, we wouldn’t have weight problems in the United States.”

Consider the work of the Obesity Action Coalition, a nonprofit organization that offers advocacy, education and support for people affected by obesity. This group is pushing the Treat and Reduce Obesity Act, which seeks to expand Medicare coverage to include screening and treatment of obesity, including coverage of FDA-approved medications for chronic weight management.

This group also fights against weight stigma, which research shows can lead to discrimination at the doctor’s office and beyond. Because of weight bias and stigma, the stereotype of overweight people being lazy and unmotivated runs rampant and can even prevent people struggling with obesity from getting the help they need. Some turn instead to unhealthy fad diets, hoping to learn how to lose weight fast. It's a journey—not a sprint. They need support along the way.

Furthermore, doctors should consider that structural racism is associated with several health disparities, including a higher BMI among Black people, according to an October 2020 study in the American Journal of Preventive Medicine. Some Black communities have less access to health education, healthful food and physical activity. Additionally, research has shown that racism itself can cause chronic stress that can lead to disease.

If you think your doctor isn’t being thorough in assessing your health, speak up. “We respect physicians. But when we feel that we’re not being treated in a way that’s respectful and with dignity, call it out,” says Thomas.

Instead of obsessing over BMI, Allison-Ottey wants women to assess how they feel : energy level, fitness, how their clothing fits and other factors. And Thomas wants women to focus on what their bodies can do. “If you exercise, your cognitive functions improve, your cardiovascular health improves and people who exercise are happier,” Thomas says.

So, move your body — no matter its size.

“Focus on what you can do and being happy,” Thomas says, “instead of focusing on what society says your BMI should be.”

Javacia Harris Bowser is an award-winning freelance journalist and essayist based in Birmingham, Alabama, and she is the founder of See Jane Write, a community and website for women who write. Javacia has written for USA Today, Heart & Soul, Good Grit, HerMoney.com, and a host of other media outlets. She’s the author of Find Your Way Back, a collection of essays that explore how she’s used writing to cope with cancer and everything else life has thrown her way. Find Javacia on Instagram and Twitter @seejavaciawrite.