Reasons Why BMI is BS
BMI refers to an individual’s Body Mass Index. It takes into account the height and weight of a person to generate a number. The general guidelines for BMI state that if your BMI is between 18.5 and 25, it falls within the healthy weight range. Less than this amount is considered underweight. BMIs greater than 25 are divided into two categories: overweight and obese. If your BMI is between 25 and 30, it falls within the overweight range. If your BMI is 30 or higher, it falls within the obesity range.
Unfortunately, these numbers are often inaccurate and misleading. While these measurements have been used since the 19th century, they are not always applicable today. This method of assessing health is narrow and outdated. In reality, health is not just influenced by the number on the scale. The influencers of health are numerous and varied including food intake, physical activity, the environment, genetics, medical care, and social circumstances.
How did BMI start?
The Quetelet index was developed in the 1830s by Lambert Adolphe Jacques Quetelet, an astronomer, mathematician, statistician, and sociologist from Belgium. The Quetelet index was a number achieved by measuring body weight in relation to height. Quetelet created this formula to give a quick and easy way to measure the degree of obesity of the general population to assist the government in allocating resources. Quetelet himself said that this calculation does not indicate the level of fatness in an individual.
In the late 20th century, researcher Dr. Ancel Keys coined the term “body mass index” based on the Quetelet index. Dr. Keys analyzed about 7,400 men from five European countries to develop the BMI standards that we know today. In 1998, the National Institute of Health approved the current BMI standards, which increased public awareness of the BMI system.
From its beginnings, BMI was supposed to be an indicator of population health. Additionally, it was only created as a justification for the need of government resources. It is crucial to reocgnize that BMI’s original creator, Quetelet, was not a health professional. Therefore, BMI was never supposed to be a marker of health, and it should not be used in this way today.
Furthermore, Dr. Keys’ work in the 20th century was based on White European males. BMI did not and does not account for race, ethnicity, gender, and age. BMI also does not consider body composition in its calculations. Based on this scale, people with more muscle will have a higher BMI, possibly putting them in the wrong health categories. This is also true for women because research shows that women generally have a higher percentage of body fat.
Let’s give an example.
It can be difficult to reject the idea of BMI at first glance when you have heard it all your life. Looking at another individual’s BMI and personal story can help demonstrate how BMI is an inaccurate representation of health. Let’s take one of the most well-known American football players: Tom Brady. In 2021, Tom Brady became the oldest quarterback to win the Super Bowl at 43 years old. To achieve such a goal, Brady’s health must be in excellent condition. The BMI scale, however, states that Tom Brady’s BMI is 27.4. This number puts him in the “overweight” category, less than 3 units away from the “obese” category. It is clear in this case that BMI is not an accurate indicator of Tom Brady’s health. His BMI does not take into account his muscle mass, waist measurements, age, and other factors. This case illustrates how BMI is not the one and only indicator of health. In fact, BMI may not be an appropriate indicator of health at all.
What is BMI today?
While BMI is the same measurement as it was a century ago, its uses and implications are varied today. The notion of BMIs may actually have caused more trouble than it is worth. Research shows that BMI significantly affects the mental health of young adults and elderly individuals. For the elderly, a 5 unit increase in BMI increases their probability of depression by 29%. Furthermore, other studies have demonstrated a positive association between a high BMI and mental health issues, including depression, eating disorders, anxiety, and substance abuse. A high BMI impacts individuals' quality of life, as many face stigma, discrimination, and fat-shaming because of their weight. Some physicians are even quick to dismiss patients with a high BMI instead of giving these patients the care that they deserve.
Developed by a mathematician and statistician, BMI was a numerical calculation and it should remain that way. It is a number, not an indicator of health or how a person should be treated. You are more than a number! You are a family member, friend, and perhaps a student or employee. Your worth is so much more than number, so don’t be fooled into thinking otherwise.
Sources:
Amin, Vikesh et al. “The impact of BMI on mental health: Further evidence from genetic markers.” Economics and human biology vol. 38 (2020): 100895. doi:10.1016/j.ehb.2020.100895
Lemond, Angela. “How BMI Came to Define Obesity, and Why This Measure Is Flawed.” Everyday Health. 17 March 2021. https://www.everydayhealth.com/diet-nutrition/bmi/bmi-flaws-history-other-ways-measure-body-weight/
Sarwer, David B, and Heather M Polonsky. “The Psychosocial Burden of Obesity.” Endocrinology and metabolism clinics of North America vol. 45,3 (2016): 677-88. doi:10.1016/j.ecl.2016.04.016