International and Swiss experts call for new obesity guidelines

Obesity needs to be diagnosed differently, say experts Keystone-SDA

A group of international doctors, including those from the University Hospitals of Geneva, says the body mass index (BMI) is not a reliable measure of health and calls for a revision of the guidelines for diagnosing obesity.

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In addition to BMI, body fat metrics – such as waist circumference or direct fat measurement – should be used, the group recommended on Wednesday in the British journal The Lancet Diabetes & Endocrinology.

BMI is calculated by dividing weight in kilograms by height in metres squared. Currently, a BMI over 30 is considered a sign of obesity for people of European origin.

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Specialists have long criticised the fact that BMI isn’t a direct measure of fat, doesn’t reflect its distribution in the body and provides no information on individual health or disease.

Why relying on BMI alone to diagnose obesity is problematic

“Relying solely on BMI to diagnose obesity is problematic, as some people tend to store excess fat around the waist or in and around their organs such as the liver, heart, or muscles,” explained Robert Eckel of the University of Colorado at Aurora, co-author of the paper.

According to him, this poses a higher health risk than excess fat directly under the skin in the arms, legs or other parts of the body. Moreover, people with excess body fat don’t always have a BMI that indicates obesity, so their health problems may go unnoticed.

The expert panel suggests using various diagnostic methods, such as measuring waist circumference, waist-to-hip ratio, or waist-to-height ratio, alongside BMI, or even directly measuring body fat. Only those with a BMI over 40 would be considered to have excess body fat without needing further confirmation.

Two categories of obesity: clinical and preclinical

Alongside the new diagnostic guidelines, the experts, led by Francesco Rubino of King’s College London, propose two new categories: ‘clinical obesity’ for chronic disease linked to lasting organ dysfunction, and ‘preclinical obesity’ for the earlier phase that presents health risks but isn’t yet a chronic disease.

Different therapeutic strategies are needed for the two phases, according to the authors. The proposal by the Commission on Clinical Obesity, which brings together doctors from various specialties, is backed by 76 learned societies and patient associations worldwide, as stated in the article.

Obesity in Switzerland

It’s estimated that over a billion people worldwide suffer from obesity. In Switzerland, the proportion has doubled over the past 30 years: in men, it has risen from 6% in 1992 to 13% in 2022, and in women from 5% to 11%, according to figures from the Swiss Federal Statistical Office. This trend is observed across all age groups.

Translated from French by DeepL/sp

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