The Sketchy Origins of the BMI: Body Mass Index

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When it comes to the Body Mass Index or BMI, have we been following an extremely flawed formula from the 1800s created by an astronomer?

The BMI seems to have become the standard of what “optimal health” looks like. You may have been confused by the number and what it actually represents.

How can you divide your weight by your height and get any idea of what your true overall health looks like?

This is a look back on where the BMI came from, why it became the standard, and why it may have caused a lot more problems than it was worth.

Who Was Adolph Quetelet?

This story starts in the early 1800s. Adolphe Quetelet was a Belgian scientist with an interest in math and statistics. He applied all his knowledge of statistics to other scientific disciplines, such as astronomy.

But Quetelet also had a love for social sciences. Could he apply his knowledge of statistics to social situations?

He published several books looking at the statistics of things like crime and marriage rates. One notable publication had to do with “the average man.”

In this work, he was trying to show that many human traits were measurable.

This work would lead to the field of “anthropometry,” which simply measures data about the human body.

This would help to define what the average person looked like. It could be useful from a public perspective, just not an individual one.

But how would you find an average weight? Tall people usually weighed more, so Quetelet thought average weight could be discovered with a simple equation:

Mass (kg)/Height (m)2

This was called the Quetelet Index and had nothing to do with health — it was purely mathematical. Here’s the first big problem: the data only came from French and Scottish people.

Quetelet developed the standard with white men and didn’t consider other races. The precedent was set that a white male standard was normal and anything else was considered less than the standard.

Statistical standards like these started out as academic but would be used for some horrible pseudoscience in the coming years.

The Insurance Companies Get Involved

Life insurance is pretty simple: if the person lives long, the insurance company collects a lot of payments. If they die early, the company loses out, but they still have to pay out to the beneficiary.

If someone was considered more likely to die early, insurance companies could charge a higher rate. They were documenting more cases of early death in highly overweight people and needed to figure out how much to charge them.

In 1910, one company noticed that the health effects of a high BMI were worse for young people than for the elderly.

According to their data, these overweight individuals with a high BMI would lead to fewer monthly payments over the course of their life.

BMI emerged as one of those predictors of premature death.

But there were obviously some major flaws. Insurance companies had only included BMI data from people who had the money and ability to buy insurance.

All the data was coming from white, well-off Americans. And different insurance companies weren’t all using the same data.

The data was also being investigated by insurance statisticians and not medical doctors.

For the medical community, biological issues surrounding obesity weren’t even fully investigated until the middle of the 20th century. The only data doctors had to go on was coming from life insurance companies.

A key problem? Everyone just assumed BMI was an accurate measure of body fat. No one had actually tested this, and any testing used flawed methods and, again, only white male test subjects.

It would remain the standard from then on.

One of the Biggest Problems With BMI Today

So its origins are pretty horrific, but BMI is still used. And it does not provide a snapshot of your health. To say the BMI formula is simplistic would be an understatement.

The equation of BMI = kg/m2 is extremely lacking in variables.

Health is not an equation: there are many factors involved. With BMI, the formula only considers height and weight. It doesn’t account for many things, such as age, overall body composition, or even your frame.

We are all built differently, and an archaic formula doesn’t consider for any of this. If you have a lot of muscle and body fat in the single digits, you could still be considered obese by BMI standards.

Muscle is metabolic, it burns calories even at rest. The more of it you have, the easier it can be to stay at a healthy body fat level. If you have a lot of lean muscle, you are probably pretty fit and active from gaining it.

Again, this is something the BMI number doesn’t reveal.

In fact, when it comes to BMI, most athletes you see who are lean and muscular are usually considered “overweight” or “obese.” Their large amounts of lean muscle, combined with an athletic frame and bone density, put them in these ridiculous categories.

A great example of this is with NFL running back Marshawn Lynch. Here are some of his NFL combine stats.

• Height: 5'11"
• Weight: 215 (98kg)
• 40-yard dash: 4.48 seconds (faster than a lot of wide receivers)
• Agility score: 11.67 (ranked him at 17th)
• Verticle Leap: 35.5 inches
• 60-yard shuttle: 11.8 seconds
• Broad jump: 125 inches
• Bench Press with 225 pounds: 20 reps
• BMI: 30

That BMI put him in the obese category… Do we really need to say more?

On the other hand, someone with a lower BMI could actually have a very high percentage of body fat and the metabolic problems associated with that. But a calculator will tell them they are considered “healthy.”

BMI is the Easy Way Out

Medical experts are extremely busy. A constant influx of patients is so time-consuming that it's hard to give each patient undivided attention.

This is where the Body Mass Index can be a great time saver. Instead of having to take genuine body fat measurements through more precise means such as water displacement, or skin calipers, a quick calculation was more appealing.

Even if it’s a flawed calculation, it could keep people moving through the door. The BMI gets you quickly in and out and keeps the revolving door moving.

It’s like you’re passing through to get this number branded on your behind.

BMI reduces us to nothing more than a number. It’s a statistic that has caused so much confusion and heartache.

It’s not rooted in genuine science and gives us no indicator of our true health status. And how can a single decimal point separate someone from being overweight to being obese?

BMI blames people for being at a certain number. It also ignores social issues, including living conditions, income, and access to quality food and healthcare.

As Usual, it All Comes Down to Money

BMI was perfect for the pharmaceutical industry. Now, they had a quick calculation that could immediately categorize people.

BMI is a terrible indicator of health. It does not reveal the dozens of other health markers that really show us where we are at. It’s also an awful indicator of actual body fat levels.

But the big pharma companies saw huge potential when you can limit everyone to a simple number. In 1998, the BMI thresholds were changed.

It’s important to point out that no one was really even sure where those thresholds should be set in the first place.

But in June of that year, the NIH decided that a BMI over 25 was considered overweight — and a BMI over 30 was obese.

BMI threshold changed overnight and 30 million people woke up the next day to find out they were now considered “overweight.”

Not surprisingly, the committee to support this change seems to be funded by pharma companies who were, of course, pushing their own weight loss drugs.

The definition of overweight and obese had changed, but no one was asking if this statistical change actually meant health problems.

Again, people were now nothing more than a number. Did anyone even look into the 25–30 BMI range to see if it was causing health problems?

Well, there were actually several studies. A quantitative analysis of over 600,000 people found the lowest mortality rates were in those with a BMI between 23 to 29.

The 25 to 30 BMI range — who had now been considered “overweight” — was not associated with higher risk.

Not surprisingly, you weren’t likely to see reports on studies such as these. Instead, you probably saw the quick headline of the new definitions of obesity, and how sick you now were.

The American Medical Association Makes it Worse

In 2013, the American Medical Association took the BMI to an even worse place. Not only could the BMI define who was considered “obese,” but obesity was now officially considered a “disease.”

This archaic formula — from when people were riding around in horses and buggies — was now defining what disease was.

An article from 2013 in the New York Times points out “there is not even a universally agreed-upon definition of what constitutes a disease.” Their decision didn’t even have any legal authority.

The thing is, the AMA had its own council that was speaking out against the inaccuracy of the Body Mass Index. They realized it was a flawed system, and that there were no symptoms specific to obesity alone.

The AMA ruled against the recommendations of their own council.

As usual, this decision benefited pharma companies who were having trouble getting insurance to cover their newly released weight loss drugs.

This decision was made right after two new obesity drugs, Qsymia and Belviq, had entered the market.

Companies marketing drugs like this could now point out to physicians — and the public — that obesity was now recognized as a disease and these drugs would save the day!

The move could also “spur more insurers to pay for treatments.”

With all of these new classifications, one-third of the country could now be considered “ill.” One day they weren’t considered sick — the next day they might have to rely on incredibly expensive drugs.

Final Thoughts

You can’t tell if someone is healthy just by looking at them, and that’s what BMI tries to do. But you can see now that its origins are sketchy, it’s the lazy way out, and it serves corporations more than you.

Life isn’t about being a number, and the Body Mass Index is nothing but that. In the end, it has not served people well and has contributed to a lot of medical weight stigma.