Understanding BMI (Body Mass Index)
We often hear clients talk about how they are nervous (TERRIFIED, actually) to go to the doctor, because of weigh-ins and conversations about BMI. To be plotted on a graph to “determine” whether they are underweight, normal/healthy weight, overweight or obese.
A simple equation: a person's weight in kilograms divided by the square of height in meters.
This hyper-simplified health determining tool creates immense fear for many of our clients, who are terrified of being categorized with certain labels, and as a result, often creates rigid rules and barriers for reaching the weight that is actually healthy for them and their bodies in recovery.
What Is BMI?
BMI, or Body Mass Index, is a mathematical equation used to determine body fat based on height and weight that applies to adult men and women.
(IMPORTANT to note that this was never a tool intended for children or adolescents, due to the major physical changes occurring during growth years and puberty.)
Limitations of BMI:
It is important to understand that there are some major flaws in using BMI measurements, as this is not information that actually tells us anything, let alone anything pertinent to health, yet has become heavily relied upon by the medical field.
The body mass index fails on multiple fronts as an appropriate and accurate tool.
Here's how:
1. The person who dreamed up the BMI said explicitly that it could not and should not be used to indicate the level of fatness in an individual.
2. It is scientifically nonsensical.
There is no physiological reason to square a person's height which is part of the formula used to determine BMI.
3. It is physiologically wrong.
It makes no allowance for the relative proportions of bone, muscle and fat in the body. But bone is denser than muscle and twice as dense as fat, so a person with strong bones, good muscle tone and low fat will have a high BMI. It also does not account for genetics, ethnicity, socio-economic factors, concurrent health concerns, or a myriad of other factors that influence NOT JUST WEIGHT, but OVERALL HEALTH.
4. It gets the logic wrong.
The CDC says on its Web site that "the BMI is a reliable indicator of body fatness for people." This is a fundamental error of logic. A high BMI does not mean an individual is even overweight, let alone obese. It could mean the person is fit and healthy, with low body fat percentages.
5. It suggests there are distinct categories of underweight, ideal, overweight and obese, with sharp boundaries that hinge on a decimal place.
That's total nonsense. To make weight so black and white is dangerous in the eating disorder community - a demographic that already tends toward rigid thinking patterns. It suggests that a pound more or a pound less would make a person change the weight category they fall into.
YOUR HEALTH IS SO MUCH MORE COMPLEX THAN A MATH EQUATION CAN EVER ACCOUNT FOR
6. Continued reliance on the BMI means doctors don't feel the need to use one of the more scientifically sound methods that are available to measure obesity levels.
7. It does not take into account fitness level, genetics, ethnicity, socioeconomic factors, age and other important pieces of information about the individual.
8. The subject pool used to study/research BMI was composed of ADULT MALES predominantly from Belgium - meaning, a tool that is applied to all genders of any ethnic background, did not study women or participants from diverse cultural backgrounds.
So, if you have ever felt defeated by hearing your BMI, know this: it does not define you, nor does it tell you how healthy you are.
Why is BMI Used in Eating Disorder Treatment?
After learning about the glaring shortcomings of the Body Mass Index tool, one has to wonder why it is still relied upon so heavily in medicine, particularly in the treatment of eating disorders.
Let’s explore the reasons together:
Screening Tool:
Simple and Quick: BMI is easy to calculate and doesn't require complex tests or expensive equipment. This makes it a quick way to screen for potential health issues related to weight.
First Step: It serves as a starting point for healthcare providers to identify if there might be a problem that needs further investigation.
Identifying Risk:
Underweight Concerns: For people with eating disorders like anorexia, a low BMI can indicate malnutrition and the need for medical intervention.
Overweight Concerns: For those with binge-eating disorder, a high BMI can highlight risks for conditions like diabetes or heart disease.
Monitoring Progress:
Tracking Changes: During treatment, changes in BMI can help track progress. If someone is underweight and their BMI starts to increase, it shows that treatment may be helping.
Setting Goals: BMI can be used to set healthy weight goals, which can be motivating and provide a clear target for recovery.
Health Indicator:
General Health: While not perfect, BMI gives a general idea of whether someone's weight might be affecting their health. It helps identify if someone might need to gain or lose weight to improve their health. (In theory).
Unfortunately, across the globe, we hear about limited resources, higher patient:doctor ratios, less time per appointment, and an increase in the overall severity of cases presenting.
This ultimately means that many healthcare providers have to find ways to quickly assess risk without the ability to spend the necessary time with each patient to complete thorough assessments about the person, their lifestyle, their environment, or their general mental health.
BMI creates a shortcut to an accurate, compassionate picture of what is ACTUALLY occurring for the patient, and in some cases, determines what the healthcare provider offers as a treatment protocol.
Who Does This Affect?
Patients who register as “overweight” or “obese” are typically more susceptible to BMI-driven treatment protocols. The advice given is often, “you need to lose weight”. A blanket statement. Without the deeper dive into contributing factors. This type of recommendation is given to youth, as well, who are presenting in those categories on the BMI chart.
Why Is This Problematic?
Although nutrition education varies by school, a 2021 survey of medical schools in the U.S. and U.K., published in the Journal of Human Nutrition and Dietetics, found that most students receive an average of 11 hours of nutrition training throughout an entire medical program.
There is little to no exploration (or identification) of eating disorder behaviours or mental health factors that are often a large contributing factor to an individuals eating behaviours.
If a person is using food as a coping mechanism, simply telling them to lose weight without exploring and providing alternate coping strategies will not lead to long term behavioural changes with food.
This type of recommendations often only creates (or confirms) the shame many people already feel as a result of their weight and/or behaviours. Many people who have been treated in this way by a healthcare practitioner admit to not seeing their doctor frequently, because of their embarrassment and lack of compassion shown to them.
This can lead to an unhealthy pattern of dieting, which can be a factor in the development of an eating disorder (where one was not yet present).
At The Holistic ED Recovery Center, we believe in treating the whole person. In order to do that, we spend as much time as necessary uncovering the potential factors that are affecting the individuals well being - not only their body weight. There are MANY NON-WEIGHT indicators of health that should be explored and recognized as well, during the journey to health and recovery.
Conclusion
In summary, BMI is used in eating disorder treatment because it's a simple and quick tool for screening, identifying risks, monitoring progress, and indicating general health. It’s limitations are many, and it should never be interpreted as an accurate measure of health… and it certainly does not define your worth!
If you are interested in exploring how we approach recovery from a more PERSON-CENTERED lens, please reach out.
We offer FREE discovery calls for anyone who is interested in recovery.
