Half a year has passed since the Lancet Commission on Clinical Obesity published its attempt to build a global consensus around a definition for obesity that distinguishes clinically significant obesity from preclinical obesity. Three new publications in Annals of Internal Medicine make it clear that this task is incomplete. Despite heroic efforts, consensus for distinguishing different levels of obesity risk beyond BMI is nowhere in sight.
The EASO Framework
Last year, EASO published a framework intended to reduce the reliance on BMI for distinguishing higher and lower risk patients. Today in Annals, Dror Dicker and colleagues show that this framework identifies more people as having obesity than BMI alone does. “But whether these newly identified adults with obesity would benefit comparably to obesity treatment as those traditionally included in treatment trials is uncertain,” they conclude.
In short, the EASO framework singles out more persons as having obesity – but not necessarily persons who need treatment specifically for obesity.
Waist Circumference
A second paper in Annals examines the possibility of setting thresholds of waist circumference to stratify BMI categories of health risk. It is a noble effort that modestly improves risk stratification. But consistency of discrimination was an issue.
A Long Way to Go
In an editorial alongside these two studies, Christina Wee, Bryan Batch, and Eliseo Guallar note that consensus on this subject is an exceedingly difficult challenge:
“Before we can build consensus on the best universal approach to define and risk stratify obesity, we need more head-to-head comparisons of the performance of these different tools in diverse populations.”
Many people are having a hard time seeing anything beyond body weight. For evidence of this, take a look at the new guidance from the American College of Cardiology. A primary focus on weight is evident in the title: “Medical Weight Management for Optimization of Cardiovascular Health.” The manuscript talks more about weight than about obesity.
Such preoccupation with weight will remain strong until a consensus emerges on better staging systems for distinguishing different levels of obesity risk. We have a long way to go.
Click here, here, and here for the three new papers in Annals. For the new ACC guidance, click here.
Hills and Ploughed Fields near Dresden, painting by Caspar David Friedrich / WikiArt
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July 08, 2025 at 9:30 am, Allen Browne said:
Obesity has many forms – % adipose tissue, where the adipose tissue is, when the high level of adipose tissue develops, ….
The goal of treatment for any disease is better health.
We have a long ways to go, but we are making progress. The obesities are many diseases and treatment is aimed at better health – now and in the future.
Allen
July 08, 2025 at 1:51 pm, Thomas George said:
Thank you for keeping us current in the evolving world of obesity, Ted!!
As an obesity specialist, I am frustrated by the continued reliance on weight and body mass index (BMI) as surrogate markers for obesity in medical and scientific practice, as it overlooks the complexity of the disease. Substantial evidence demonstrates that prolonged, untreated obesity significantly increases the risk of developing a wide array of obesity-related conditions. Rather than emphasizing weight and BMI, clinical assessment should prioritize direct measurement of excess adiposity, the principal defining feature of obesity, and stage disease progression according to the presence and severity of obesity-related complications.
Excess adiposity contributes to morbidity through two primary mechanisms: fat mass disease, which encompasses the physical and compressive effects of increased fat tissue, and adiposopathy, or “sick fat disease,” which reflects the metabolic and endocrine dysfunction of adipose tissue. These mechanisms are implicated in the pathogenesis of over 230 obesity-associated conditions, including several site-specific cancers.
Given these insights, it may be prudent to revise established staging systems such as the Edmonton Obesity Staging System, replacing BMI with more precise measures such as body fat percentage and fat mass. This paradigm shift would better align clinical practice with the underlying pathophysiology of obesity, facilitating earlier intervention to prevent, halt, or reverse the progression of obesity-related diseases.
The limitations of BMI as a biomarker for obesity are well-documented, particularly its inability to distinguish between fat and lean mass or to account for fat distribution, as well as not accounting for differences in culture and sex.
Early and accurate identification of excess adiposity is critical for effective prevention and management of obesity-related complications.
A pathophysiology-based approach supports more individualized and effective treatment strategies.
Thanks again for all you do!
Thomas