Report aims to clarify the definition of obesity

A statement introducing the report said: “Despite evidence that some people with excess adiposity have ill health due to obesity, obesity is generally considered a harbinger of other diseases, not a disease in itself.

“The idea of obesity as a disease remains therefore highly controversial.

“In addition, current BMI-based (body mass index) measures of obesity can both underestimate and overestimate adiposity and provide inadequate information about health at the individual level. 
  
“This Commission sought to define clinical obesity as a condition of illness that, akin to the notion of chronic disease in other medical specialties, directly results from the effect of excess adiposity on the function of organs and tissues.

“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.”

The report was endorsed by the Royal College of Physicians for setting out a clinically meaningful definition of disease in obesity as well as a definition of the objective criteria for its diagnosis.

Dr Kath McCullough, the Royal College of Physicians special adviser on obesity, said: “Obesity is a global health challenge of immense complexity and consequence, requiring a more nuanced and clinically sound framework to better understand and address its impact. The Lancet Diabetes & Endocrinology Commission on Clinical Obesity has made a significant stride forward by creating a clinically meaningful definition of obesity and establishing clear criteria for its diagnosis. This lays a strong foundation for treating obesity with the same medical rigour and compassion as other chronic illnesses.

“For too long, we have relied on BMI as a simple measure of obesity, which has often misrepresented the condition and fails to fully reflect how excess body fat impacts a person’s health. The commission’s distinction between pre-clinical and clinical obesity represents a vital step forward, highlighting the need to identify and intervene early while providing appropriate care to those already experiencing severe health impacts.

“We fully support the commission’s recommendations to improve how obesity is diagnosed by including direct measurements of body fat, along with proven methods like waist size and other body measurements. We also support their focus on using treatment plans that are based on solid evidence and matched to how severe the condition is, aimed at improving health and preventing obesity-related illness from leading to organ damage. Equally important in both the prevention and treatment of obesity is the recognition of the pervasive weight stigma that undermines effective care. The commission rightly calls for a shift in societal attitudes, as well as education for healthcare professionals and policymakers, to ensure obesity is addressed with compassion and without bias.

“This work challenges us to adopt an approach that is both scientifically grounded and patient centred. By doing so, we can pave the way for better health outcomes, reduce the burden of obesity-related diseases, and restore dignity to individuals living with obesity. I commend the Lancet Commission on Clinical Obesity for providing a thoughtful and transformative roadmap for change."

Read the report in The Lancet Diabetes & Endocrinology

Read more about type 2 diabetes