Global Experts Propose Comprehensive Approach to Obesity Diagnosis Beyond BMI

Experts worldwide are suggesting a fresh approach to defining and diagnosing obesity. This new method reduces reliance on the body mass index (BMI) and aims to better identify those needing treatment for issues caused by excess body fat. Released on Tuesday night, the recommendations propose combining BMI with other measures like waist circumference and health problems linked to extra weight.

Obesity affects over 1 billion people globally, with about 40% of adults in the US experiencing it, according to the US Centres for Disease Control and Prevention. Dr. David Cummings, an obesity expert at the University of Washington, stated, "The whole goal of this is to get a more precise definition so that we are targeting the people who actually need the help most." He is one of the 58 authors of the report published in The Lancet Diabetes and Endocrinology journal.

New Diagnostic Categories

The report introduces two new diagnostic categories: clinical obesity and pre-clinical obesity. Clinical obesity involves meeting BMI and other markers, along with evidence of organ or tissue issues due to excess weight. Conditions like heart disease, high blood pressure, or chronic joint pain could qualify someone for treatments such as diet changes or medications.

Pre-clinical obesity refers to individuals at risk for these conditions but without current illnesses. The report highlights that BMI has been a flawed measure, often misclassifying individuals. For instance, athletes with high muscle mass might have a high BMI despite normal fat levels.

Potential Impact on Obesity Classification

Preliminary analysis suggests that under the new criteria, around 20% of those previously classified as obese might not meet the definition anymore. Conversely, about 20% with serious health effects but lower BMI would now be considered clinically obese. Dr. Cummings noted that while this won't drastically change obesity statistics, it will better identify those with significant excess fat.

The new definitions have received support from over 75 medical organizations globally. However, it's uncertain how quickly they will be adopted in practice due to potential costs and workforce implications. A spokesman for AHIP mentioned it's too early to determine how these criteria will influence coverage or policies.

Challenges in Implementation

Dr. Katherine Saunders from Weill Cornell Medicine pointed out practical challenges in implementing these definitions. Measuring waist circumference may seem straightforward, but varying protocols and inadequate training complicate matters. Additionally, distinguishing between clinical and pre-clinical obesity requires comprehensive health assessments and lab tests.

"For a new classification system to be widely adopted, it would also need to be extremely quick, inexpensive, and reliable," she said. Kate Bauer from the University of Michigan expressed concerns about public understanding, stating that people prefer simple messages and this differentiation might not lead to significant changes.

Dr. Robert Kushner from Northwestern Feinberg School of Medicine acknowledged that redefining obesity will take time but sees this as an initial step in starting discussions on the topic.