A commission of international experts has redesigned the conditions for the diagnosis of obesity so that it is no longer limited to the body mass index (BMI).
- An international commission proposed a recasting of the diagnosis of obesity.
- Experts no longer limit the diagnosis to the body mass index to define the obesity stage.
- The diagnosis of obesity involves measuring body fat, either direct or by indicators like the waist.
Obesity progresses strongly around the world. The incidence in adults has more than doubled since 1990, and even quadrupled in adolescents. According to the WHO, one in 8 people through the globe suffered from obesity in 2022.
To better take care of this “epidemic”, a commission of 58 experts from different countries and medical specialties and patients has developed a recasting of the diagnosis of obesity, presented in a report published in the journal The Lancet, January 14, 2025. BMI is no longer the only marker of the disease.
Obesity: other criteria are added to the BMI for the diagnosis
Currently, the BMI is the major indicator to assess the corpulence of a patient. But, it is not fine enough, according to the experts. Indeed, if the index makes it possible to predict an obesity greater than 40 kg/m2 Without any concern, it lacks precision for the lower scores.
The Commission thus recommends that the diagnosis of obesity also involves the direct measure of body fat, “If it is possible” or anthropometric measurements such as the waist, size/hips or size/height tower. For example, the threshold of the waist to be diagnosed with obese is from 102 cm in men and 88 cm in women.
In addition, to establish a diagnosis of preclinical obesity, that is to say a chronic and systemic disease, the patient must present one or the other of two main criteria:
- functional involvement of an organ or tissue due to obesity (clinical signs, functions of one or more tissues or organs);
- The significant reduction in daily activities, adjusted at age: mobility, daily activities (toilet, clothing, continence, meals).
Obesity has been redefined
Beyond rethinking the tools for the diagnosis of obesity, the Commission also wanted to redefine obesity. It distinguishes between clinical and preclinical obesity. The National Academy of Medicine detailed it in a press release. The first is “A chronic, systemic disease, linked to an excess of adiposity in many organs and tissues whose functions are altered, with or without distribution abnormality or function of the adipose tissue itself”. Its causes are multifactorial. In addition, clinical obesity can cause “Serious, metabolic complications (diabetes), cardiovascular, stroke, renal, cancer and mortality proportional to fat”.
“Preclinical” obesity on its side corresponds to excessive adiposity without damage to other tissues and organs. She also presents a “Variable, but generally increased risk, to develop clinical obesity and several other non-transferable diseases (for example, type 2 diabetes, cardiovascular disease, certain types of cancer and mental disorders)”.
Experts recommend management of patients with clinical obesity offering “A treatment of obesity itself as well as associated clinical damage” In order to prevent the progression of the disease and its complications. Persons who have received a diagnosis of preclinical obesity must be offered a “Management associating recommendations, in particular physical activity and food, medical monitoring and possibly treatment intended to reduce the risk of evolution towards clinical obesity”.
“By providing a new definition and a new diagnostic framework, the commission identifies when obesity is a risk factor (preclinical obesity) and when it represents an autonomous disease (clinical obesity)”specifies theeditorial accompanying the report published in The Lancet.
“Adopting a new and more precise approach to identifying obesity and changing societal perceptions will take time and efforts, but at the heart of these proposals is the objective of improving the lives of people suffering from Obesity.conclude the authors.
