BMI part 2- the history of BMI.
Hi, everyone, it’s Ali from Ok2BeFat! And it’s time for some fat activism basics.
In this video I will be discussing weight and weight loss. I will also be using the words “obesity” and “overweight” in the context of discussing and quoting scientific studies, even though these are not words I would normally use.
In this series, I’ll be talking about BMI, or the body mass index.
If you haven’t watched part 1 yet, I suggest you go back and watch it now, so we’re all on the same page.
This is Part 2. The history of BMI.
Fatness wasn’t always considered bad. Around the end of the 1800s, there was a negative shift in cultural attitudes towards fat people, when before that time fatness had been fashionable and had even been celebrated.
Until the 1890s fatness was very fashionable, especially among women. The Victorian ideal for a woman was of a mother at home in her proper place with her children. Fatness was viewed as a natural consequence of frequent pregnancies and frequent pregnancies were very much to be desired.
According to Peter Sterns in Fat History, Elizabeth Cady Stanton was praised for her round features, approvingly called “as plump as a partridge” while her fellow suffragette Susan B. Anthony was criticized for being gaunt and too thin.
Doctors urged weight gain for a number of nervous disorders, and actresses were praised for their fashionably rounded arms and faces. For men, fat bodies were socially read as belonging to men with fat bank accounts and both a fat body and a fat wallet were to be desired.
There are a lot of factors that play into the cultural slide towards the demonizing of fat, but in Big Fat Lies Glenn Gaesser points to the life insurance industry as one of those factors.
In order to make as much profit as possible, life insurance companies were looking for ways to separate people into higher and lower risk categories for premature mortality. They needed a way to try to predict if someone has a higher chance of dying early.
A side note-
Generally when we are talking about mortality rates in the context of fatness, what we mean are people dying early, where early is considered to be before 65 years old, because in the United States 78% of all deaths are of people who are over the age of 65.
It’s important to make sure that everyone knows we are talking about premature mortality even when people leave out the word “premature”, otherwise you get people who say things like “all fat people are going to die” without seeming to grasp the idea that all the thin people are also going to die because being thin does not make you immortal.
So you have life insurance companies in the 1890s trying to figure out who might die early because they want to take in more insurance policy payments than they pay out in claims when someone dies. Because that is how insurance companies make money.
This is way before the type of data collection we have today. In the 1890s and well into the 1900s, the insurance companies didn’t have access to hardly any information about their policyholders. But what they did have was weight- public scales for weighing began to appear in 1891.
Because weight is such an easy figure to collect and track, the industry took this information and tried to match it up to its policyholders to see if there was any correlation to premature death.
This gives us the first height-weight tables in the 1890s, with the assumption that anything over the average weight was bad and contributed to premature mortality.
But how did the insurance companies collect and interpret this data? Does it hold up to scientific standards? Well, no.
The two largest examinations undertaken by these insurance companies were riddled with flaws. These studies are the 1959 Build and Blood Pressure Study and the 1979 Build Study.
For one thing, the demographics of life insurance policy holders did not accurately represent the population at large, because the people paying for life insurance are richer and whiter and more male than the general population.
But even worse, the insurance companies defined mortality for their purposes as a policy being cashed in, and not as we would usually define it — as the death of a single person. If someone purchased 5 insurance policies, his death would count 5 times, which skews the actual sample size.
And even though the studies are meant to cover a large range of time —
1935 thru 1954 for the first study and 1954 thru 1972 for the second — these studies do not measure a fixed population over a fixed period of time. A person who bought a policy in 1936 and someone who bought one in 1952 would both be included in the 1959 study, which is a ridiculous oversight for a study purporting to measure longevity.
But for years, these unscientific height and weight tables from life insurance companies were used to determine who was supposedly too fat.
In 1972, Ancel Keys sought to displace the by now discredited life insurance tables with something more scientific. And for that, he turned to a formula originally authored by in 1832 by Adolphe Quetelet, a Belgian mathematician who came up with the equation we now call BMI.
Quetelet was something of a Renaissance man, with interests in various arts and sciences. He spoke six languages. He was fascinated by astronomy, founding the Brussels Observatory and serving as its director for 50 years.
But his true love was statistics. He loved gathering and studying data on large groups of people, believing that there was fundamental truth to be found in the study of these large groups, rather than focusing on the experiences of any one person.
He wanted to quantify the average man. But to Quetelet, average didn’t mean boring or mediocre — average was the definition of perfection. In his book, A Treatise on Man and the Development of his Faculties, Quetelet says —
“If the average man were completely determined, we might consider him as the type of perfection; and everything differing from his proportion or condition, would constitute deformity or disease…or monstrosity.”
Quetelet was not studying fatness or health in any of the ways we would talk about today. Rather, he was interested in what constituted an average size over a population.
It also seems important to mention that the population that led to the original BMI calculation was a few hundred residents of Brussels — not exactly a group representative of the population of the entire world.
For a long time, the Quetelet equation was known to a few scientists but it didn’t go much further than that.
Then, in 1972, Ancel Keys published a study of over 7,400 men from 5 different countries called “Indices of Relative Weight and Obesity” that concluded that Quetelet’s index was the best indicator of the extent of body fat of an individual person. Keys is the one who named the calculation the body mass index.
This study popularized BMI and in 1985, the National Institute of Health began using it as a way to define obesity.
A side note —
This is the part where I tell you that Ancel Keys is kind of a mixed bag for fat activism. He conducted the Minnesota Starvation Experiment, which has findings that are frequently cited by fat activists regarding the dangers of yo-yo dieting, as well as the mental toll a continued calorie deficit can have.
Keys clearly didn’t intend for BMI to be used as an indicator of individual health. He conducted a review of the major studies on fatness and premature mortality in 1980 that found a risk of premature mortality increased in both underweight and overweight people, but only at the very extremes.
But Keys also called fatness “disgusting as well as a hazard to health” and “ethically repugnant”. He became obsessed with the idea that an overconsumption of dietary fat caused heart attacks, and it has been suggested that his study into fat consumption played fast and loose with the data — specifically that he only included the results that confirmed his original hypothesis.
He also made an enormous amount of money off of one of the first low fat cookbooks “Eat Well and Stay Well”. His conclusions were used by the US Senate to set national nutrition standards that helped set off the low-fat dieting craze that began in the 1970s.
Is it possible that the overlap of a period of time of national emphasis on high carbohydrate and low fat meals and a period of time when overall weight levels appear to have increased may mean that the one has caused the other?
Well, it’s certainly possible, but we don’t know. There may not be a way to ever know for sure, based on the large number of variables present in such a question, but it does present an interesting counter narrative that has yet to be fully explored.
It certainly seems that for Doctor Keys, somewhere along the way, the amount of dietary fat consumed by a population got conflated with the perceived number of fat people in a given population. He just assumed that the existence of fat people was caused by consuming fat.
Some of the assumptions Keys originally made are ones that we still see playing out today, in ways that harm fat people.
Back to the timeline-
In 1985, the National Institutes of Health officially took up BMI as the standard way to measure obesity, while acknowledging that the data on fatness and premature mortality was disputed and sometimes contradictory. The statement they put out notes that perhaps the greatest suffering caused by fatness is the “enormous psychological burden” it causes.
You’ll have to excuse me for finding some bitter amusement in that. A document that helped to advance fatphobia by making BMI the tool to mark who is too fat — a tool that is used every day, around the world to discriminate against fat people in medical settings to devastating and often deadly consequences — that this document would hand wave concern in the direction of the mental suffering of fat people?
It seems almost beyond belief.
Back to 1985 — the NIH meeting to adopt the new BMI standards included people with ties to the weight loss industry.
We’ll find as we go on that just about any conference to discuss fatness as a medical problem always includes representatives of the weight loss industry, an industry that makes billions each year off of the “enormous psychological burden” they help cause.
The standards set by the National Institutes of Health in 1985 put overweight at a BMI of 27.8 for men and 27.3 for women.
Then in 1998, the NIH went back to BMI again and changed the standards to 25 for overweight and added a new category for obese, which began at 30.
This change consolidated the prior two standards into one for all genders, races and ages, even though the ability of BMI to predict body fat is not consistent among genders or among people of different races, or at different ages.
Many people who would have been considered an average weight were pushed into the overweight range overnight.
The only peer reviewed research the 1998 Obesity Task Force cited in their recommendation to lower the BMI cutoffs was a study that suggested that raising the overweight cutoff to 40 would be more in line with the actual research.
Let me repeat that, because I want to make sure we all heard it properly.
The task force that lowered the BMI standards in 1998 — the only peer reviewed research they included in their report recommending that the cutoffs for a so-called ‘normal’ weight category be lowered — that study recommended that the cutoffs be raised and raised significantly. To a BMI of 40.
Not lowered. Raised. And yet the standard was lowered anyway. Why?
Well, 7 of the 9 participants in the NIH’s 1998 Obesity Task Force were directors of weight loss clinics, while also having multiple other financial ties with the weight loss industry as a whole.
The change to a more stringent standard obviously served to benefit that industry, by making more people subject to dire health warnings from their doctors.
And that brings us up to the present day.
More fear means more money. Inducing a moral panic over fatness, ramping up fatphobia, hurting fat people — this is huge money for the weight loss industry.
The weight loss industry has continued to use the lowered cutoffs to turn enormous profits. They turn agony into cash, 60 billion dollars worth, every year, just in the United States alone.
And that’s the end of Part 2- the history of BMI.
Please see the notes for a list of the sources I consulted for this series.
If you have specific questions about BMI, leave a comment below!
Always and forever, I have to thank all the fat activists who came before me and those who will come after.
And thank you also to my supporters on Patreon, especially the ones scrolling by now.
See you soon for part 3.
Adolphe Quetelet and the Evolution of Body Mass Index (BMI) — by
Beyond BMI — by Jeremy Singer-Vine
Commentary: Origins and evolution of body mass index (BMI): continuing saga — by Henry Blackburn and David Jacobs, Jr
NIH statement- “Health Implications of Obesity”
Implicit anti-fat bias among health professionals: is anyone immune? — by B A Teachman and K D Brownell
Implicit and Explicit Anti-Fat Bias among a Large Sample of Medical Doctors by BMI, Race/Ethnicity and Gender — by Janice A. Sabin, Maddalena Marini, and Brian A. Nosek
The big fat truth — by Virginia Hughes
Body of Truth by Harriet Brown
Losing It by Laura Fraser
The Obesity Myth by Paul Campos
The Great Starvation Experiment by Todd Tucker
Fat History by Peter N. Stearns
Health at Every Size by Linda Bacon, PhD
Ok2BeFat logo art by Jen Lightfoot (http://www.jenlightfoot.com/)