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BMI - the Bullsh*it Measuring Index

Sep 12, 2021
Firstly, let's identify what BMI is. While we refer to it as the Bullsh*it Measuring Index here at IPA, it actually stands for Body Mass Index.
Put simply, it’s a way of categorising people by their height and weight. It’s calculated by dividing your weight (in kilos) by your height in (meters squared).
The result is a number that puts you on one of five places on a quantitative scale:
  1. ‘Underweight’: <18.5
  2. ‘Normal’: 18.5 – 24.9
  3. ‘Overweight’: 25.0 – 29.9
  4. ‘Obese’: 30.0>
  5. ‘Morbidly Obese’: 40>
Your BMI score will have been frequently noted by healthcare professionals throughout your life and this is because it determines the access to healthcare you are entitled to. For example, if your BMI is classed as in the ‘Obese’ category then under the current NHS guidelines would be refused access to fertility treatment. Using such cut-off actively discriminates against individuals health needs based solely on their weight and perpetuates fatphobia!

How and when was it created?

The BMI equation was developed nearly 200 years ago in the mid 1800s by a Belgian astronomer (note: not a doctor) Adolphe Quetelet. It was originally known as the Quetelet Index.

Quick facts:

  • The aim of the equation was to find the ‘average man’ to help create the social ‘ideal’. 
  • Quetelet found his ‘averages’ by taking the measurements of white men only.
  • The Quetelet Index was never intended to be used by doctors/in medicine. 
  • Quetelet’s Index was used as a measurement as a scientific justification for eugenics (the systemic sterilization of disabled people, autistic people, immigrants, poor people, and people of colour).

BMI & Healthcare:

The modern term Body Mass Index (BMI) was first coined in a medical paper published in the Journal of Chronic Diseases in 1975 by a guy called Ancel Keys. 

Ancel himself said: “If not fully satisfactory, it is at least as good as any other relative weight index as an indicator of relative obesity”, suggesting that even he knew it wasn't that great back then. 
By 1985, the US National Institute of Health had revised their definition of ‘obesity’ to be tied to individual patients’ BMIs.
BMI became the measure of choice, replacing the standard insurance tables, and with that, this imperfect measurement was enshrined in U.S. public policy and then quickly adopted by the UK health system.
In 1998, overnight 40 million Americans either became classified as overweight, or moved from overweight to obese, without gaining a single pound. This is because the BMI thresholds were changed by the National Institute of Health without anyones prior knowledge to accommodate the insurance company accessibility markers.
This meant that MEGA savings could be made on healthcare costs by disallowing certain treatments/access to care to anyone with a higher BMI.

BMI – A Few of the Many Issues

  • Countless scientific studies have confirmed its lack of efficacy due to it not accounting for individual differences e.g. race, muscle mass, bone density etc.
  • The World Health Organisation suggests that BMI could underestimate the health risks for Asian communities.
  • The Endocrine Society (a global community of physicians and scientists dedicated to accelerating scientific breakthroughs and improving patient health) suggests BMI overestimates fatness and health risks for black people.
  • BMI is a measure built by and for white people – it can’t therefore accurately account for the whole of society.


This over simplistic and universal measure of ‘health’ creates divides and contributes significantly to weight and healthcare stigma without scientific basis.

Weight stigma in healthcare (based on BMI) can lead to misdiagnosis and refusal of
treatment, sometimes with fatal consequences:
An example of this is the case of Ellen Maud Bennett who was a Canadian woman who went to the doctors numerous times as she felt very unwell. Ellen was only ever advised to lose weight. Once she became seriously unwell, she finally received medical attention and it was discovered that she had cancer and sadly only had a few days to live.
Her dying wish at the young age of 64 was for weight stigma to be challenged so that access to healthcare is accessible to all regardless of their size.

BMI – The Good News

A group of UK MPs are calling for the use of the BMI to be scrapped!!
The legendary Women and Equalities Committee warned that the impact of the pandemic, both on individuals with eating disorders and also those at high risk of developing one, has been “devastating”.
The MPs' report highlighted that using the restrictive and over-simplistic measure of BMI as a main health determiner is no longer appropriate. When using BMI, patients are inappropriately put on weight loss programmes prompted solely by their score which ultimately contributes to issues such as eating disorders, poor mental health
and diet culture mentality.
The committee also branded the government’s obesity strategy as “dangerous” for
those with negative body image. We have written more about this harmful government campaign in our recent Dear Boris blog post. We share the letter we wrote to the Prime Minister, challenging this 'public health' campaign. In short, the new nationwide weight loss campaign is triggering eating disorders, perpetuating diet culture and causing harm.

We still have a LONG way to go, but knowing that these incredible MPs are fighting the good fight is a step in the right direction. 

To find out more about the history of the BMI and its link to racism and fatphobia, sign up to our Diet Culture Dropout Course.