Jamy Ard

Is Obesity a Diagnosis or a Conspiracy?

BMI is one of those topics in the obesity realm where many people agree in many ways. Yet it can inspire some passionate arguments. A prime example of these disagreements came right to the top of the workshop on BMI at the Roundtable on Obesity Solutions at the National Academies yesterday. In quick succession, we heard presentations that described two extremes. Either BMI benchmarks were the product of a conspiracy to “medicalize” obesity or they are merely screening tools for a much more involved process required in diagnosis of the very real chronic disease of obesity.

The BMI Conspiracy

Katherine Flegal took on the task of describing the BMI conspiracy with a timeline dating back to the 1990s, when the International Obesity Task Force and the World Health Organization produced reports to establish a BMI threshold of 25 for overweight and 30 for obesity. This, apparently, is where the heart of the conspiracy lies.

Those thresholds were driven by industry funding, Flegal suggested. Not only that, they were arbitrary. But, quoting the New York Times, she said it handed the pharmaceutical industry “a lucrative market for diet pills on a silver platter.”

The Screening Tool

Donna Ryan presented a different picture, describing BMI thresholds as a screening tool that points to the possibility of obesity. Regarding obesity, she said “this is a disease. And if for some reason you don’t want to believe it, just bear with me for a few minutes.”

But her real point was that BMI is nothing more than a convenient tool. Without a clinical assessment, it’s meaningless. It’s just a simple number derived from height and weight that can point to the possibility of adiposity that might harm a person’s health. It is not racist, as some suggest, but certainly it can be misused in pernicious ways.

So everyone seems to agree that BMI is a simplistic tool that has big limitations. Some people want to discard it. Others want to use it cautiously. Still others want to use it to prove that obesity is the product of a conspiracy and not a legitimate diagnosis.

The Embedded Conspiracy

In reality, the conspiracy afoot that harms us all is invisible. It is implicit human bias that pervades all discussions of obesity and harms people every day. Overcoming weight bias and stigma should be the focus of our concerns. Not a conspiracy of numbers. When someone wants to label and devalue us, the problem is not the excuse they use for it. It’s the bias they harbor, whether they know it or not.

Click here for more on this workshop and be sure to come back for the full posting of video and presentations from it in a week or two. The content of the entire day was rich and goes well beyond the BMI conspiracy discussion. For more on efforts to find better ways to define obesity, click here.

Jamy Ard at the Roundtable on Obesity Solutions, photograph by Ted Kyle

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April 5, 2023

8 Responses to “Is Obesity a Diagnosis or a Conspiracy?”

  1. April 05, 2023 at 8:28 am, Angie Golden said:

    This roundtable was some of the best 5 hours of thoughtful presentations I have attended on obesity in quite some time! I encourage anyone that didn’t attend to come back when the videos post. Except for a few who still want to use biased language (non person first) it was great listening.

  2. April 05, 2023 at 8:28 am, John DiTraglia said:

    There is a movement afoot in the AMA to discontinue the BMI as a required vital sign and they stopped promulgating BMI in grammar school. So that’s progress.

  3. April 05, 2023 at 9:54 am, Kate Bauer said:

    I agree Ted that the history of BMI is not the most compelling argument to think about its validity today, although the context clearly matters and highlights the racist nature of weight bias and the thin ideal, and makes us consider motivations driven by profit rather than public health.

    I disagree though that discussing the validity of BMI and how to define obesity is a distraction from addressing weight stigma. When a clinician looks at a number or a growth chart and uses that to provide guidance, guidance that may not be relevant to your health, that’s weight stigma. When the media reports that X% of the country is obesity based only on BMI and it’s costing our country billions of dollars, that spurs weight bias. Yes, larger individuals are stigmatized by people who never know their BMI, but there’s lots of ways that our focus on BMI and the cutpoints to define someone as having obesity have fed into discrimination.

    • April 05, 2023 at 10:30 am, Ted said:

      I agree with you that the misuse of BMI is one of the ways that health systems and providers stigmatize people living with obesity.

  4. April 05, 2023 at 11:01 am, Katherine Flegal said:

    Just a correction. I did not say anything about a “conspiracy’ and did not use that word. I presented factual information that is well documented but that a lot of people are not aware of. It is perfectly clear that the IOTF was funded by drug companies, just as James said. That is not a conspiracy, but it was something that was not clearly presented at the time. It represents a potential conflict of interest that was not openly obvious. Also, as James article makes abundantly clear, WHO did not initiate the conference and did not have any interest initially. I was told by a WHO staffer that the WHO lawyers sent a letter to James telling him to stop implying that the IOTF was somehow sponsored or funded by WHO itself.

    • April 06, 2023 at 3:47 am, Ted said:

      Thanks for clarifying that you did not use the word conspiracy. But you did describe, in a very detailed way, a secret plan by a group to do something you view as harmful. The definition of a conspiracy is a secret plan by a group to do something harmful.

  5. April 05, 2023 at 9:50 pm, John Dixon said:

    BMI is very poorly understood. It is a useful metric but it is simply one sign. Not a diagnosis. It is our best simple sign of body fatness. Yes flawed but nothing perfect.

  6. April 06, 2023 at 2:17 pm, DONNA RYAN said:

    The 2013 Obesity Guidelines spent 5 years reviewing the evidence around cut points as identfiers of cardiovascular morbidity and mortality and ended up endorsing BMI 25<30 as overweight and BMI 30+ as obesity – same as those “arbitrarily” selected years before. So there is evidence to support these as good screening tools for the population. But then we need to evaluate individual patients by assessing waist circumference, presence of signs and symptoms of excess abnormal body fat to make our clinical diagnosis.

    On another note Jamy Ard reinforced the concept of knowing where we are in the weight trajectory. We need to record highest adult weight and highest adult BMI. GREAT IDEA!!!