Virgilio Brocchi

All Agree on Moving Past BMI, But Differ on the Details

It was easy to see this coming. Our top prediction for the new year was that the Lancet Commission on Clinical Obesity would be big news and the spark for a big debate. The news splash was unmistakable. From 92 countries all over the world, more than 3,000 persons lined up for the launch event. Media attention is still strong a week later. Everyone seems to agree that the time is right for moving past BMI in the clinical diagnosis of obesity. But from there, everyone seems to have a different take on the details of how to do it.

Yes, the intense debates have begun about defining clinical obesity – just as we predicted. And as we stated before this all started, the debates will not be settled anytime soon.

Pediatric Sticking Points

No stranger to controversy about obesity, the American Academy of Pediatrics stepped right up to this one. Having recently spent years to develop a clinical guideline for pediatric obesity, the Academy was not eager to see it displaced. Sandra Hassink, who is an author the AAP guideline, commented:

“We recommend that pediatric clinicians continue to follow recommendations for screening, evaluation and treatment of pediatric obesity as outlined in the evidence-based 2023 AAP Clinical Practice Guideline for the Evaluation and Treatment of Children and Adolescents With Obesity (CPG).”

Another author of the AAP guideline offered some specific issues with the Lancet recommendations:

“We have concerns about some specific items missing in these criteria that are relevant to pediatrics such as genetics, precocious puberty, and mental health. In addition, we have concerns about some of the selected criteria and their application and relevance across the age span, particularly young children.”

What Is Pre-Clinical Obesity?

And then there is the natural discomfort with the concept of preclinical obesity. Many people worry that the concept of  Arya Sharma, author of the Edmonton Obesity Staging System (EOSS), sees the potential for a real setback from the Lancet Commission. He wrote:

“I think this report is a step back from the Canadian guidelines or even the EASO framework in Nature Medicine. The Canadian and EASO framework are already clear on the fact that obesity is a rather straightforward clinical diagnosis requiring an impairment in health (i.e. BMI etc is not enough to establish a diagnosis or indication for treatment). Pre-clinical obesity is identical to EOSS Stage 0. This report adds nothing but confusion.”

No Debate: BMI Alone Does Not Define Clinical Obesity

Consensus is not easy. But even the harshest critics of the Lancet Commission report seem to agree: More than BMI is necessary to define a clinical diagnosis of obesity. We fully expect that pediatricians will continue to define clinical criteria for pediatric obesity care. We expect robust discourse and a continuing evolution in the clinical definition of obesity.

But the bottom line here is quite simple. People who live with obesity know quite clearly when obesity is impairing their health. That is different from having a risk for future disease. Now clinicians and experts need to catch up and do the hard work of agreeing on clear diagnostic criteria for this disease.

This is movement in the right direction. The work of the Lancet Commission can help us get there.

Click here for the commission report, here, here, and here for further perspective.

Virgilio Brocchi, painting by Umberto Boccioni / WikiArt

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January 23, 2025

3 Responses to “All Agree on Moving Past BMI, But Differ on the Details”

  1. January 23, 2025 at 8:03 am, Allen Browne said:

    Unhealthy amounts of adipose tissue in unhealthy places is bad whether it is causing signs or symptoms yet or not. Just like high blood pressure, elevated insulin levels, etc, etc, etc. And counselling and healthy living habits are good for health, but they rarely change the biology behind the unhealthy adipose tissue. And the situation needs to be treated with tools that work no matter the age, sex, ethnicity, or socio-economic situation. It is actually quite simple. Treat obesity like we do other diseases. Educate about the disease. Fight bias and stigma.

    Have a good day.

    Allen

  2. January 23, 2025 at 9:20 pm, Angela GOLDEN said:

    I love that Lancet group want us to move beyond BMI BUT they didn’t even label obesity as a disease – just an illness – how much more confusing can a respected group cause is my question. I was very disappointed that they didn’t name obesity as the chronic disease that we have all been working so hard to get our colleagues, patients AND insurers to understand. It felt like 3 steps forward and 4 steps backward.

    • January 24, 2025 at 3:18 am, Ted said:

      Angela, the whole point of the commission was to define the clinical criteria for diagnosing the disease of obesity. From the executive summary:

      “The specific aim of the Commission was to establish objective criteria for disease diagnosis, aiding clinical decision making and prioritisation of therapeutic interventions and public health strategies.”

      So, no. I cannot agree that the commission does not label obesity as a disease. It goes beyond that. It offers criteria for clinical diagnosis of the disease.