Doctors propose new definitions of obesity that would move away from BMI
In a significant move, major medical groups are advocating for a shift in how doctors diagnose obesity. A report published in Tuesday’s issue of The Lancet Diabetes & Endocrinology by 58 international experts and individuals with lived experience proposes a new definition and diagnostic criteria for clinical obesity. The current methods of diagnosing obesity are deemed inadequate in accurately assessing an individual’s health status.
The international Commission on Clinical Obesity, responsible for the proposed new definitions, describes it as a more nuanced approach. The report introduces 18 diagnostic criteria for clinical obesity in adults and 13 criteria for children and adolescents. Dr. Katherine Morrison, a pediatric endocrinologist and professor at McMaster University in Hamilton, emphasizes the importance of moving away from solely focusing on weight and height to prioritize overall health.
Traditionally, obesity has been determined by the body mass index (BMI), which calculates weight in relation to height. However, BMI fails to differentiate between fat and lean mass, leading to misclassifications where individuals who are fit and healthy may be labeled as overweight. The report highlights examples of misclassifications, including heavyweight champion boxers with substantial muscle mass.
Moreover, BMI does not consider fat distribution, which can significantly impact health risks. Excessive fat storage in critical areas such as the waist or around organs poses a higher health risk compared to fat stored under the skin in areas like the arms or legs. The new definition of “clinical obesity” focuses on ongoing signs or symptoms of reduced organ function attributed to obesity alone, emphasizing the impact on daily activities.
Dr. Sean Wharton, medical director of the Wharton Medical Clinic for Weight Loss, supports the proposed changes, which move beyond BMI cutoffs based on a narrow demographic. He stresses that obesity is more complex than just body size, involving inflammation in fat cells. By reframing obesity as a disease, there is hope to reduce judgment towards individuals with larger body sizes.
The endorsement of the new definitions by Diabetes Canada, American Heart Association, and weight-loss support group TOPS reflects the growing acceptance of this paradigm shift. The report also opens up possibilities for the use of GLP-1 class drugs like Wegovy and Ozempic in treating obesity, potentially influencing health insurers to consider coverage based on individual risk factors.
The ultimate goal of this initiative is to bring about a change in medical practice and mindset, encouraging a more holistic approach to diagnosing and treating obesity. By prioritizing health over weight alone, individuals can receive tailored treatment plans that may include lifestyle modifications, medications, or surgical interventions.
