Every day in doctor’s offices around the country, patient measurements are taken in an antiquated fashion the moment they’re asked to step on a scale and their weight is put into a chart that estimates the Body Mass Index (BMI). The BMI is a generalized metric based on the ratio of weight to squared height that’s been proven ineffective and dangerous, yet is still the norm.
If someone’s weight lands above the BMI cutoff for obesity, the doctor will likely inform the patient that they are at risk for all sorts of illnesses, and the patient will be told to—of course—“lose weight.” Many of us have heard phrases like these, and they tend to incite shame as doctors often deliver these statements without tact or empathy.
So, why is BMI the standard and why doesn’t it work? Let’s take it back to the 1800s…
The first thing to know about the BMI is that it was created by a Belgian mathematician—not a doctor. In the 1830s, Lambert Adolphe Jacques Quetelet set out to find the “l’homme moyen” or the “average man.” His belief was that if you could take thousands of measurements and compare them, you could find the “ideal weight.” Through calculating these samples, he found that weight typically increases in relation to the square height of a person, and the study became the standard BMI we use today.
There’s just a couple major problems with this. In an experiment meant to be for the “average man,” let it be known that Quetelet only conducted this on participants who were western European men. Not only that, but that experiment and its results were never meant to be applied to individuals. BMI was originally created with the purpose of studying populations and, therefore, it is commonly agreed upon by many health professionals that BMI is not an accurate measure of health.
Breaking it down further, BMI is a measurement determined by two physical characteristics: height and weight. The formula is simple: BMI = (weight in kilograms ÷ height in meters) BMI reflects only these two physical characteristics of a person while disregarding all other considerations.
Yet, most people believe that someone with a normal BMI is healthy and someone with a high BMI (categorized as “overweight” and “obese”) is unhealthy. This supports the false narratives that 1) the bigger an individual is, the more unhealthy they are, 2) all fat people are unhealthy, and 3) all thin people are healthy—all of which are simply not true.
The reality is that individuals can be healthy or unhealthy at any size, a principle commonly referred to as Health at Every Size (HAES).
For many decades, the definition of physical health has been the most common definition of “health,” period, but the real meaning of “health” is much more complex. The Center for Disease Control says that health is determined by a number of factors, including genetics, behavior, environmental and physical influences, medical care and social factors.
BMI should not be considered the sole determinant of health but should instead be only one deprioritized consideration alongside mental health, emotional and spiritual wellbeing, financial security, environmental safety, physical and mental ability, behavioral habits, cultural influences, and more.
Using BMI as the main indicator of individual health is killing people.
Using BMI as a main (if not only) indicator of health is not only theoretically problematic, but it also negatively impacts higher weight individuals substantially.
When determining a person’s health or diagnosis, many healthcare practitioners ignore and gloss over higher weight people’s ailments, pointing to an individual’s physical appearance and BMI rather than doing a thorough physical exam or mental wellness check.
This occurance is an example of weight stigma or weight bias which can be defined as “discriminatory acts and stigmatizing beliefs directed towards those perceived to carry excess weight.”
BMI as a whole is an obvious example of a systemically imposed and socialized form of weight bias. BMI is harmful to all people, but it especially impacts those in larger bodies. As a direct result, a 2012 study shows that the majority of doctor visits for patients in larger bodies are recorded as lasting a shorter length of time than visits from folks in thinner bodies for the same ailment.
This is problematic because people in larger bodies are therefore more likely to:
1) Get sick/injured and stay that way
2) Die from an illness that was not caught or caught at later stages
3) Avoid the doctor and medical facilities due to medical trauma
Any time a single number defines a whole human being, there is a huge risk that the human will be overlooked. And there is simply no scientific evidence that the BMI should be used as the main indicator of an individual’s health. It’s not logical, ethical, or precise, but one thing’s for certain—it is bullsh*t.
Serena Nangia has been working as an advocate for eating disorder recovery for over 8 years. She is the Marketing & Communications Manager at Project Heal, the leading nonprofit in the U.S. focused on equitable access to eating disorder and mental health treatment.
