BMI Isn’t Just Wrong. It’s Lazy, Biased, and Misleading
BMI. Just three little letters, but somehow they’ve become the gatekeepers of healthcare, the justification for higher insurance premiums, and the spark behind countless shame spirals in doctor’s offices.
Spoiler alert? It’s crap.
In this article, we’re breaking down the real story behind BMI: where it came from, why it was never meant to define health, how it took over medical systems, and, most importantly, what we should be focusing on instead.
Where BMI Really Came From (And It Wasn’t a Doctor)
Let’s take it back to the 1830s. Adolphe Quetelet, a Belgian astronomer and mathematician, not a physician, created what we now know as the Body Mass Index. But he didn’t invent it to assess health. He was trying to define “l’homme moyen,” or “the average man.”
And by “average,” he meant white, European men. Quetelet’s obsession was with identifying the ideal physical proportions of a population, not individuals. He even wrote that anything deviating from the average was a sign of deformity or disease.
So yeah… not exactly a body-positive pioneer.
His formula (weight divided by height squared) was a statistical shortcut, not a clinical tool. And it stayed that way for over a century.
How BMI Got a Rebrand (But Still Didn’t Deserve It)
Fast-forward to 1972. Ancel Keys, a respected nutrition researcher, tested a handful of formulas to estimate body fat in large population groups. He decided that Quetelet’s ratio worked best statistically (for large groups, not individuals) and officially renamed it the Body Mass Index.
The sample? 7,424 healthy adult men.
No women. No older adults. No ethnic or cultural diversity. No variations in body type.
So from the jump, BMI was never validated for the full spectrum of human bodies. It was convenient math, not inclusive science.
But that didn’t stop it from being adopted like gospel.
The Day Millions Became “Overweight” Overnight
Now here’s where things take a sharp turn.
In 1998, the National Institutes of Health (NIH) released new obesity guidelines. They lowered the threshold for “overweight” to a BMI of 25 and declared anyone with a BMI of 30 or higher “obese.”
No new scientific breakthrough. No major health revelation. Just a policy change.
And just like that, millions of Americans woke up newly “overweight.” Their health didn’t change. Their habits didn’t change. Only the definition did.
This wasn’t a medical revelation. It was reclassification by spreadsheet.
Worse? The panel behind this decision included members of the American Society for Bariatric Surgery, a field that stands to gain financially from more people qualifying for obesity-related procedures.
The panel chair, Dr. Xavier Pi‑Sunyer, would later disclose financial ties to multiple pharmaceutical companies involved in obesity and diabetes treatments.
I'm not saying it was a grand conspiracy, but I am saying the guideline documents contained no conflict-of-interest disclosures. And in a decision that affects millions of people’s access to care, that lack of transparency should raise some serious questions.
Why BMI Caught On (Even Though It Shouldn’t Have)
It’s not because it’s accurate. It’s because it’s easy.
Doctors can calculate it in seconds. Insurance companies can use it to justify higher premiums or deny coverage. And health systems can plug it into charts with zero nuance.
Never mind that it doesn’t measure muscle mass, doesn’t account for fat distribution, and can’t distinguish between an elite athlete and someone with serious metabolic concerns.
It’s literally just height and weight. That’s it.
Why BMI Doesn’t Work (Like, At All)
Let’s say this loud for the people in the back: BMI doesn’t measure health.
A marathon runner with dense muscle and low body fat could be labeled “overweight,” while someone with low muscle mass and high visceral fat could score “normal.”
It doesn’t ask:
Where is your fat stored?
How much of your weight is muscle?
How are your hormones doing?
What’s your genetic or ethnic background?
How old are you?
A single number cannot possibly account for the full human experience.
Even the American Medical Association (AMA) admitted in 2023 that BMI was built on outdated, white-centric data and does not account for sex, race, or body composition.
Translation?
The people who once pushed it are now slowly backing away, like it’s an awkward ex at a coffee shop.
What the Research Actually Says
Let’s hit pause on opinions and look at the actual science.
A massive 2013 meta-analysis published in JAMA reviewed nearly 3 million people across 97 studies and found:
People in the “overweight” BMI category (25–29.9) had lower all-cause mortality than those in the “normal” range.
Even people with Class I obesity (BMI 30–34.9) had no significant increase in death risk compared to “normal” BMI individuals.
So yeah, that whole “higher BMI = you’re doomed” narrative? Not holding up so well under scrutiny.
To make things even more complicated, the World Health Organization had to create lower BMI thresholds for Asian populations, because health risks showed up at different points.
So not only is BMI flawed, it’s not even globally consistent.
What We Should Measure Instead
Your health isn’t a fraction. It’s a full-body symphony, and every part plays a role. Here’s what gives us a much clearer picture:
Physiological Markers
Waist-to-height ratio
Waist circumference
Body fat percentage (especially visceral fat)
Metabolic Labs
A1c and blood glucose
Lipid panels (cholesterol, triglycerides)
Inflammatory markers like CRP
Fitness & Function
Strength, endurance, mobility, and flexibility
Cardiovascular capacity (can you walk up stairs without gasping?)
Recovery speed after exercise or stress
Lifestyle & Mental Health
Sleep quality
Stress resilience
Emotional regulation and support systems
Access to care and rest
How you feel in your body, not just how it looks
BMI doesn’t capture any of this. But these things? They actually reflect health.
The Bottom Line
BMI is a relic, built before modern medicine, before we understood hormones, and definitely before we valued body diversity. It’s a shortcut that became a standard because it was cheap, easy, and convenient for systems, not for people.
If your doctor still relies on BMI like it’s gospel? It might be time to find someone who knows your health is more than a math problem.
You are not a label. You are a story, a system, a beautifully complex human being.
Your care should reflect that. Because this isn’t about shrinking to fit a category It’s about rising up to unveil the beautiful Beast within YOU.
Check out the YouTube Video Here:
Sources & References
BMI, mortality, and risk
Flegal KM, Kit BK, Orpana H, Graubard BI. Association of All-Cause Mortality With Overweight and Obesity Using Standard Body Mass Index Categories: A Systematic Review and Meta-analysis. JAMA. 2013;309(1):71–82.
https://jamanetwork.com/journals/jama/fullarticle/1555137?utm
History & construction of BMI
Keys A, Fidanza F, Karvonen MJ, Kimura N, Taylor HL. Indices of relative weight and obesity. Journal of Chronic Diseases. 1972;25(6–7):329–343.
https://www.sciencedirect.com/science/article/pii/0021968172900276Eknoyan G. Adolphe Quetelet (1796–1874)—the average man and indices of obesity. Nephrology Dialysis Transplantation. 2008. PubMed https://pubmed.ncbi.nlm.nih.gov/17890752/
1998 BMI guideline shift
National Institutes of Health (NIH). Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults: The Evidence Report. 1998.
https://www.nhlbi.nih.gov/files/docs/guidelines/ob_gdlns.pdfNational Institutes of Health (NIH). The Practical Guide to the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults. 2000. (Mentions American Society for Bariatric Surgery members in the working group.)
https://www.nhlbi.nih.gov/files/docs/guidelines/prctgd_c.pdfNCBI Bookshelf. Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults. (Provides searchable access to guideline methods, author list, and policy changes.)
https://www.ncbi.nlm.nih.gov/books/NBK2003
Potential conflicts of interest & key individuals
Pi‑Sunyer FX. The Medical Risks of Obesity. Postgraduate Medicine. 2009;121(6):21–33. (Includes disclosed financial relationships with Amylin, Arena, Novo Nordisk, Novartis, Orexigen, VIVUS.)
https://www.researchgate.net/publication/40033636_The_Medical_Risks_of_ObesityABOM (American Board of Obesity Medicine) – Distinguished Leaders bio: https://www.abom.org/dvteam/dr-xavier-pi-sunyer/ (notes he’s been “a leader in obesity medicine” and led the first obesity treatment guidelines). https://www.abom.org/dvteam/dr-xavier-pi-sunyer/
NIH/NHLBI Clinical Guidelines (he chaired the national panel): https://www.nhlbi.nih.gov/files/docs/guidelines/ob_gdlns.pdf nhlbi.nih.gov
BMI as a limited tool
American Medical Association (AMA). AMA adopts new policy clarifying role of BMI as a measure in medicine. 2023.
https://www.ama-assn.org/press-center/ama-press-releases/ama-adopts-new-policy-clarifying-role-bmi-measure-medicineCitation: Strings, S. (2023). How the Use of BMI Fetishizes White Embodiment and Racializes Fat Phobia. AMA Journal of Ethics, 25(7), E535–E539. https://doi.org/10.1001/amajethics.2023.535
Centers for Disease Control and Prevention (CDC). About Adult BMI.
https://www.cdc.gov/bmi/index.html
Population differences in BMI thresholds
World Health Organization (WHO). The Asia-Pacific Perspective: Redefining Obesity and Its Treatment. 2000.
https://iris.who.int/bitstream/handle/10665/206936/0957708211_eng.pdf
Cultural and ethical context
Adele Jackson-Gibson. The Racist and Problematic History of the Body Mass Index. Good Housekeeping. February 23, 2021. Read article:https://www.goodhousekeeping.com/health/diet-nutrition/a35047103/bmi-racist-history/goodhousekeeping.com
