Rethinking Obesity Diagnosis: Why BMI Alone Isn’t Enough

A recent Lancet Global Commission report calls for an overhaul of how obesity is diagnosed, pointing out that Body Mass Index (BMI) alone is not a reliable measure. The report proposes adding other measurements like waist circumference and waist-to-hip ratio to improve the accuracy of obesity diagnosis.

BMI has traditionally been used to diagnose obesity, with a value above 30 indicating obesity for people of European descent. However, the Lancet experts argue that BMI alone is not an honest indicator of a person’s health. It may result in a misclassification, leading to unnecessary diagnoses and potential neglect of individuals with obesity who may not exhibit health issues.

The report emphasizes the need for a more nuanced approach to obesity diagnosis, particularly by introducing two new categories of obesity: ‘clinical obesity’ and ‘pre-clinical obesity’. Clinical obesity refers to cases where the condition causes persistent health issues or organ dysfunction, while pre-clinical obesity refers to individuals with elevated health risks, but no signs of immediate illness. This distinction allows healthcare professionals to offer personalized care, from early interventions to appropriate risk management.

The new diagnostic criteria, which include additional measures beyond BMI, could lead to better healthcare resource allocation, more timely treatments for those with clinical obesity, and tailored prevention strategies for those in the pre-clinical stage. This approach could help reduce the risk of misclassification and ensure that people receive the most appropriate care.

One of the key arguments presented in the report is that the current all-or-nothing view of obesity as a disease is flawed. As Francesco Rubino, chair of the commission, explained, some people with obesity maintain normal organ function and overall health, while others may already experience serious health complications. Thus, understanding obesity as a spectrum of health risks, rather than a binary disease or non-disease, would provide a better foundation for managing the condition.

Obesity has a profound effect on a person’s quality of life, impacting sleep, mobility, and fertility, while also increasing the risk of serious health conditions such as diabetes, heart disease, and cancer. The report’s recommendations seek to refine obesity diagnosis, reduce misclassification, and ultimately lead to more effective treatment and prevention strategies.

In conclusion, the Lancet Global Commission’s report advocates for a paradigm shift in how obesity is diagnosed and treated, recognizing the complexity of the condition. By adopting a more holistic approach that takes into account different aspects of health and personal circumstances, this framework aims to improve outcomes for people living with obesity around the world.