Girl's Powerful Note Explains Why BMI Is Outdated

by Lara Rutherford-Morrison
Thanapol Kuptanisakorn / EyeEm/EyeEm/Getty Images

At a school in Indiana, an eighth-grade girl was given an assignment in which she had to calculate her body mass index, a measurement of weight in relation to height. Instead of giving a number, the student wrote about why BMI is outdated and inaccurate as a measure of obesity and of general health. She perfectly captures why BMI is a flawed system, and why using it to create labels — from “underweight” to “obese” — can be damaging for young people.

The student’s letter was posted on Facebook by cartoonist James MacLeod, who wrote that he is a friend of the girl’s mother. “Her daughter had to do a middle school project that involved body-mass-index,” he said. The Centers for Disease Control and Prevention (CDC) define BMI as “a person's weight in kilograms divided by the square of height in meters” A high score “can be an indicator of high body fatness,” the CDC claims, and the scale divides people into four categories: “underweight,” “normal weight,” “overweight,” and “obese.” Nevertheless, the CDC clarifies that BMI “is not diagnostic of the body fatness or health of an individual.”

MacLeod wrote that even though his friend's daughter is "a strong and muscled athlete,” her “BMI came out as ‘obese.’” For her project, instead of calculating her BMI, as she was assigned to do, the girl explained just why body mass index is an inaccurate measure of health:

BMI is an outdated way of defining normal weight, under weight, over weight, and obesity by taking one person's height divided by their weight. One of the formula's obvious flaws, explains Alan Aragon, the Men’s Health Weight Loss Coach and nutritionist in California, is that it has absolutely no way of discriminating [between] fat and muscle. So, let's say there is a fairly athletic woman who maintains a decent diet, she's five feet, six inches, and she weighs 190 pounds, but 80% of her body is muscle. That doesn't matter when calculating BMI! This woman's BMI would be 30.7, and she would be labeled obese. Does that make sense to you? Because it sure doesn't make sense to me.
How could someone who stays fit, eats healthy, and has a low metabolism be in danger of heart disease and diabetes? Oh, that's right, because she isn't in danger of obesity and heart disease. This woman is active and healthy and she is the furthest thing from obese.

She goes on to explain why having young people calculate their BMI in a school setting is especially problematic, writing,

... BMI is an outdated way of determining a person's body health, and it's a measurement that should not be used in a school setting where students are already self-conscious and lacking confidence in their unique bodies.

The student describes her own struggles with body image — and explains that her BMI doesn't reflect her health:

Now, I'm not going to even open my laptop to calculate my BMI. And I'll tell you why. Ever since I can remember, I've been a "bigger girl" and I'm completely fine with that; I'm strong and powerful. When you put a softball or a bat in my hand, they are considered lethal weapons. But, at the beginning of the year, I started having very bad thoughts when my body was brought into a conversation. I would wear four bras to try and cover up my back fat, and I would try to wrap ace bandages around my stomach so I would look skinnier. So my lovely mother did what any parent would do when they noticed something wrong with her child, she took me to my doctor. My doctor and I talked about my diet and how active I am.
He did a couple tests and told me I was fine. He said though I'm a bit overweight, he's not going to worry about me based on how healthy I am. So this is where I don't calculate my BMI because my doctor, a man who went to college for eight years studying children's health, told me my height and weight are right on track.

She ends on an inspirational note:

I am just beginning to love my body, like I should, and I'm not going to let some outdated calculator and a middle school gym teacher tell me I'm obese, because I'm not. My BMI is none of your concern because my body and BMI are perfect and beautiful just the way they are.

Images: Thanapol Kuptanisakorn / EyeEm/EyeEm/Getty Images; MacLeodCartoons/Facebook; Giphy