The BMI Is Racist And Useless. Here's How To Measure Health Instead
If a research group today
conducted a study on a single gender or ethnic group, critics would be
quick to point out that its findings couldn’t reasonably be applied to
anyone outside of that gender or group. It seems like basic logic,
right?
Unfortunately,
such is the case with the Body Mass Index (BMI), a weight-to-height
ratio used by health care providers, insurance companies and the
scientific community.
There
is growing criticism for the use of BMI. For example, it doesn’t take
body composition (fat versus muscle) into account, and a person’s weight
doesn’t correlate directly with their health. However, there’s not much
mainstream discussion about its racist roots or the way it furthers the
oppression of and discrimination against certain groups.
A growing number of experts believe it’s time to change that.
The BMI is inherently racist and sexist.
The
racist roots of the BMI go back a long way. Created by Belgian
mathematician Adolphe Quetelet in 1832 as the “Quetelet Index,” the
scale was created using data from predominantly European men to measure
weight in different populations.
Although
Quetelet noted that it was a population-level tool and not meant to be
used on individuals, physiologist Ancel Keys reintroduced the
calculation in 1972 as the Body Mass Index, and it has since been
adopted by the medical community as a way to measure individual health. A
BMI outside the “normal” range (18.5-25) is considered less healthy,
and an indicator of greater health risks.
While the BMI has countless failings as a reliable tool, racism is chief among them, said Sabrina Strings, an assistant professor at the University of California, Irvine.
“It
is racist, and also sexist, to use mostly white men within your study
population and then try to extrapolate that and create norms and
expectations for women and people of color,” Strings told HuffPost.
“They have not been included in the initial clinical analyses, and
therefore their actual health outcomes cannot be determined by these
findings.”
In short, the way BMI is being used is unscientific because of its origins and the homogenous population it was created from.
Weight standards have long been used to perpetuate racism.
In her book ”Fearing the Black Body,”
Strings outlines the history of body standards and the ways in which
thinness was used to uphold white superiority as recently as the early
20th century.
She
describes how the thin bodies of northern and western Europeans were
upheld as the ideal, while the often larger bodies of eastern and
southern Europeans, as well as Africans, were considered signs of their
inferiority. All of this was before we really knew anything about the
(still blurry and confounding) relationship between weight and health.
The modern BMI and its categories ― underweight, normal, overweight and
obese ― have inherited much of that racism.
“Even
after all of the work that I’ve done and the work that I’ve read about
the creation of these weight categories, I’ve long wondered, ‘Who is
this even based on?’” Strings said. “This 18.5-25 ‘normal’ BMI category
that they arbitrarily came up with ― what is that even about? There’s
something so strange about that. I feel almost certain that they were
not researching people in places like Samoa, where people can be
healthier at much heavier weights.”
“There
are so many ramifications of trying to create one normative table for
the diverse people of the world,” Strings added. “The whole thing is
preposterous.”
Making assumptions about a person’s health based on their BMI is preposterous.
Racism aside, BMI just isn’t a very good measure of a person’s overall health.
“At present day, [BMI] has been widely adopted by the medical world as a shorthand for healthy or unhealthy,” said Jennifer Gaudiani,
an internal medicine physician and certified eating disorder specialist
based in Denver, Colorado. “That fact is unscientific and harmful.”
For
one thing, it can blind physicians to a patient’s actual medical
conditions. Many males with anorexia nervosa go undiagnosed because they
are technically within the “normal” BMI category, Gaudiani said. The
same thing happens to people at higher weights, who often don’t get
screened for eating disorders despite things like significant recent
weight loss, symptoms of malnutrition or reported eating disorder
behaviors.
Gaudiani described another
instance where a former patient of hers had lymphoma that was written
off by her former doctor as “part of her fat neck” until it was stage 4.
While Strings and
Gaudiani both pointed out that weight is linked to certain medical
conditions, they emphasized that being at a certain weight doesn’t make a
person healthy or unhealthy.
The experience of racism can affect BMI.
It’s
important to note that while the average adult American BMI falls into
the “overweight” category, there are marked differences between ethnic
groups. According to the Centers for Disease Control and Prevention,
the prevalence of “obesity” (a BMI over 30) is highest among Black
adults, followed by non-Black Hispanic adults. But it’s discriminatory
and unfair to make blanket statements without examining why this is the
case.
“The question
is, what contributed to higher weight across an entire [ethnic]
population? The answer lies in poverty, in minority stress, in
experienced traumas related to food inaccessibility and fear and worry
in the household about safety or financial security,” Gaudiani said. “It
lies in the propulsion of diet culture onto certain groups in ways that
start weight cycling from a really early age and do not honor body
diversity.”
“That
sets up in them a body consciousness and fearfulness or maybe even
dieting pattern, that may indeed affect metabolism and, later in life,
body weight,” Guadiani said.
What’s more, just the experience of racism can affect a person’s weight and BMI.
“I think that racism has a multi-system impact on the body,” said Lesley Williams,
a family medicine physician and certified eating disorder specialist
based in Phoenix, Arizona. “It’s waking up every day and dealing with
micro- and macro-aggressions that you’re maybe not even familiar with
but your body is absorbing ... It has an impact on stress levels, which
can then increase cortisol levels, which then impacts the body’s
composition.”
In turn, those at higher BMIs experience even more discrimination.
While
discrimination and lack of access to quality medical care can affect
BMI, they can also simultaneously be the result of a higher BMI ― an
endless cycle.
Williams
explained that many doctors believe that when a person is at a higher
BMI, it is not only their right but their obligation as a doctor to try
and intervene: to encourage the patient to lose weight, discuss the
patient’s body size and eating habits without the patient’s permission,
and address this “issue” of weight before discussing whatever medical
problem the patient may have come in for.
“That’s doing harm, and can negatively impact someone’s mental and physical health,” Williams said.
“I’ve
had so many patients who have specifically sought me out in the past
because I advertise that it’s a safe environment, who have been avoiding
health care because they have felt that it is unsafe,” Williams added.
“I hear time and time again, ‘My physician wouldn’t listen to me. I had
this myriad of complaints that had nothing to do with my weight, and all
they wanted to do was talk about my weight, and I was not being served,
and I’ve just elected not to go back.’”
As
Gaudiani mentioned, this can lead to legitimate health issues going
unchecked and unmonitored, which in itself can greatly worsen health
outcomes. Yes, a person’s weight might serve as one data point in their
medical profile, but no single number can determine how healthy someone
is overall.
“We cannot use weight as a marker of health,” Gaudiani said. “It just does not correlate, except on the very extremes.”
Unfortunately,
there’s no easy substitute. Both Gaudiani and Williams agree that the
answer isn’t to just replace the BMI with another basic measurement ―
say, taking a person’s muscle mass or body fat percentage and using that
instead. These too are only single factors, and can’t predict health
outcomes.
Instead,
Williams thinks that doctors must take all of a person’s health markers
into account when determining their health. That includes factors like
their background, their stress levels, their access to food and dietary
habits, any underlying health concerns or conditions, their relationship
with movement and exercise and more.
Of course, this takes more time and doesn’t come out to a single number that can be entered into a chart.
“I
think BMI is used because it’s a very blunt tool, if you will, and it’s
easy,” she said. Instead of making assumptions based on a patient’s
BMI, she focuses on whatever issue brought them to her office, collects
the data she needs, and targets her intervention based on those
specifics. It might be a little more time-consuming, but it’s also more
accurate and patient-centered.
The
BMI won’t disappear overnight, nor will racism or discrimination
against those at higher weights. But the number of physicians and other
experts beginning to reject, or at least seriously question, its
validity as a tool for measuring health is growing. While we all work to
break down racism and racist systems in America, we must also hold the
medical community accountable for their role in perpetuating these
systems through the use of flawed tools like BMI.