BMI: More Than Just a Number?

Body Mass Index, a common way to evaluate student health, and its impact on self-esteem is examined in this piece.

Kristen Kinzler, Staff Writer|March 11, 2019

Melina Bowser

NAEye wonders, is the potentially skewed information BMI provides worth the damage?

Every year, we have that day in gym class where we don’t have to change into our PE clothes, are handed free snacks, and get to hang out with our friends in between waiting in some lines for health screenings. Overall, it sounds kind of fun, like it’s not much of a problem. All kids have to do is give some measurements. No big deal, right?

Well, for some, the BMI screening is a nightmare. It preys on their insecurities in a public setting filled with their peers. Being aware of your health is important, but the worst part is, BMI may not even be accurate or helpful at all.

BMI stands for Body Mass Index. It’s a number based off of one’s weight to height ratio. Twenty-one states across the country require all public schools to conduct a BMI test, Pennsylvania being one of them.

The BMI test gives every student a number. Anything less than 18.5 is underweight, 18.5 to 24.9 is normal, 25 to 30 is overweight, and an individual with a number over 30 is considered obese. The test, however, can’t always tell the difference between fat and muscle in the body and doesn’t account for small differences, such as bone density. Since muscle is heavier than fat, someone who is strong or built could have a BMI that is actually considered unhealthy. This skews all of the measurements and doesn’t ensure students get correct information about their own bodies.

A study conducted classified 1,400 men and women’s weight categories by their BMIs. Then, with proper equipment and further testing, it was determined that about half of the women and a quarter of the men were given an incorrect weight category based off of their BMI.

Our school clarifies this in an informational paper given to students about the testing. They also explain that it is just a number and should not define you. However, that doesn’t always register if the number is handed to someone already insecure about their body. Logically, that shouldn’t have much on an effect on a teen’s daily life. But emotionally, it can become a number to obsess over– a number that screams they’re not good enough.

And it’s a number that may not even be accurate.

Already, 1 out of every 10 teenage girls suffer from some type of an eating disorder, and 49.5% of all teenagers say they normally have low self-esteem. For some of these girls, even stepping on a scale can be a trigger and make their disorder worse.

Imagine if getting weighed was something that made you feel sick to your stomach. Imagine if it was enough to make you not want to eat for days ahead of time, or if it brought on loads of anxiety. Now, imagine you were asked to step on a superscale in front of your whole gym class.

Terrifying, isn’t it?

Our phys ed teachers do a tremendous job at keeping students informed about the inaccuracies of this test and are experts at confidentiality, but, still, the concept stands. No matter what, it can be scary– and for no good reason.

Additionally, 95% of all teenagers said that they have felt inferior or “not enough” at least once before. When prompted to give their reasons for such feelings, 59% said it was because of their appearance, and another 35% said it was because of their size. So, this is clearly all a very big deal for adolescents. We should consequently be treating it as such.

However, our state is not recognizing the severity of this issue. If they were, they wouldn’t rely on something that is wrong so much of the time.

Because BMI has no consistency. It doesn’t make sense half of the time. And something this important, something that could impact a student’s self-esteem, needs to be accurate. Otherwise, we shouldn’t be doing it at all.

This isn’t a North Allegheny issue. It’s a Pennsylvania issue. It’s a twenty-one-state-across-our-country issue. Size and weight hit too close to home for a lot of kids. So, why are we forcing a test that publically, and sometimes inaccurately, puts kids in a weight class and exposes on their insecurities?

Turns out, NAI’s solution is to conduct an additional test– the Body Composition screening.

Mr. Schmidt, a Physical Education teacher, clarified that BMI is required for the state, but Body Composition is something that North Allegheny chooses to add on.  

“We found too many kids that were being flagged as unhealthy because their BMIs were too high,” He said, “So we started doing this to show them they were actually healthy.”

The school uses a Bioelectrical Impedance Analysis (BIA) machine to measure Body Composition. They are then handed a receipt that provides them with information like body type, fat percentage, impedance, and fat mass. BIA is one of the quickest ways to measure Body Composition. But the quickest method may come at a cost.

BIA works by sending an electrical current through your body. It measures the resistance that the current encounters as it moves through. Someone with more muscle most likely has more water in their body. The current travels easily through the water. Fat provides more of a resistance to the current. So, by measuring how easily the electricity flows, the machine can formulate some data on body health.

However, research has shown that since the electrical current naturally will follow the path of least resistance, it can sometimes miss large areas of fat. It’s possible it will skip right over the area and travel through other internal tissue.

Even if the Body Composition was completely accurate, it may not make a difference. A study conducted from 2007 to 2012 in New York City public schools found that girls who were classified as obese were highly unlikely to proactively change their behavior and rarely showed signs of getting out of that weight category. So, even after we ignore the potentially damaging risks of telling a student they’re obese, it still may not matter.

Pennsylvania began requiring BMI screenings in 2005 for all public school students. Further research has been done and more facts have come to life. Doesn’t that mean it’s time we re-examine how we measure student health?

Simply, there are a lot of uncertainties when it comes to any kind of body measurements, even the more “reliable” ones. So, at the end of the day, it’s hard to trust any of the methods that can possibly be done in school. That’s exactly why Pennsylvania should consider enacting more holistic approaches for student health screening; as demonstrated, sometimes, these methods have limitations, which can paint an otherwise healthy student, as unhealthy.

Our current evaluation methods shouldn’t be something we just accept as part of our curriculum or state mandates. It’s something we should question. Something we should recognize. Something we should be calling out–  like everything else in our constantly changing world. It’s something we need to make sure every student with a BMI number knows.

Being healthy and providing the correct tools to students is important. Placing an increased weight on a simple number that may not even be right is not.

So, at the end of the day, take all of these measurements in context. Recognize that you’re not alone in any feelings of discomfort, annoyance, or maybe even a little outrage towards BMI.

Know that the only measurement of health that you should judge yourself upon is how you good you feel and how happy you are, along with advocating for and seeking test results which give a more accurate picture of health.

That’ll tell you a lot more than any over-simplified number.