for years, the medical community has debated whether obesity should be classified as a standalone disease rather than merely a risk factor for conditions like diabetes, heart disease, and certain cancers. while obesity undeniably contributes to poor health outcomes, the reality is nuanced—many individuals classified as obese exhibit no signs of illness. This raises the question: Is obesity, in itself, a disease that warrants specific treatment? The answer remains far from straightforward.
The conversation gained momentum in 2023 with the introduction of GLP-1 weight loss drugs, such as semaglutide (marketed as Ozempic). These medications offered a new middle ground between conventional lifestyle interventions and invasive surgical procedures. As The Economist noted, this breakthrough made it crucial to determine which individuals with obesity are truly “sick” and require medical intervention.
A pivotal progress in this debate came from a group of 56 medical experts, organized by the Lancet Commission. Their goal? To redefine obesity in a way that distinguishes between those who are healthy despite their weight and those whose obesity has become pathological. Their findings offer a fresh outlook on diagnosing and treating this complex condition.
Traditionally, obesity has been measured using the Body Mass Index (BMI), a simple calculation based on weight and height. A BMI over 30 classifies someone as obese. However, this method has its limitations. As a notable example, athletes with high muscle mass frequently enough fall into the “obese” category despite being in peak physical condition. Additionally, BMI fails to account for where fat is stored in the body. Visceral fat, which surrounds internal organs, poses far greater health risks than subcutaneous fat, which lies just beneath the skin. The Lancet Commission’s recommendations address these shortcomings.
The commission proposes a new diagnostic framework for what they term “clinical obesity.” This approach requires two key elements. First, it incorporates additional measurements like waist circumference, waist-hip ratio, or waist-height ratio to complement BMI.Even better, advanced scanning technologies can directly assess body fat distribution. Second, for a diagnosis of clinical obesity, there must be objective signs of reduced organ function or impaired ability to perform daily activities, such as bathing, eating, or dressing.
The commission identified 18 specific diagnoses linked to clinical obesity, including respiratory distress, obesity-induced heart failure, and joint pain. They also noted dysfunction in organs like the liver, kidneys, and reproductive systems. Individuals without these symptoms are placed in a “preclinical obesity” category. While not currently ill, they face an elevated risk of developing clinical obesity and related health issues. However, they are not immediate candidates for drug treatment.
Francesco Rubino, a professor of metabolic and bariatric surgery at King’s College London and a member of the commission, described this reclassification as a “radical change.” He emphasized the next step: identifying which of the approximately 1 billion people globally classified as obese under the old definition now qualify for clinical obesity. Preliminary estimates suggest this could apply to 20-40% of them.
The commission’s framework has already garnered support from major health organizations, including the American Heart Association and the Chinese Diabetes Society.However, its integration into medical practice and public perception will take time. As the conversation around obesity evolves, this new approach promises to reshape how we understand, diagnose, and treat this pervasive health issue.
