The global report calls for a more precise definition of obesity than BMI

There is a risk that too many people will be diagnosed as obese when a “more accurate” and “nuanced” definition is needed, report of global experts says.

Doctors should consider the overall health of overweight patients rather than simply measuring their body mass index (BMI), the report says.

Those with chronic health conditions caused by their weight should be diagnosed as ‘clinically obese’, while those with no health problems should be diagnosed as ‘non-clinically obese’.

It is estimated that more than one billion people worldwide live with obesity, and prescription weight loss medications are in high demand.

The report, published in The Lancet Diabetes & Endocrinology journal, is supported by more than 50 medical experts from around the world.

“Obesity is a spectrum,” says Professor Francesco Rubino of King’s College London, who led the group.

“Some have it and manage to live normally, function normally.

“Others can’t walk well or breathe well, or are confined to a wheelchair with significant health problems.”

The report calls for “reframing” obesity to distinguish between patients with the disease and those who remain healthy but are at risk of developing the disease in the future.

Currently, in many countries, obesity is defined as the presence of BMI over 30 – a measurement that estimates body fat based on height and weight.

Access to weight-loss drugs such as Wegovy and Mounjaro is often limited for patients in this category.

In many parts of the UK, the NHS also requires people to have a weight-related health condition.

But BMI doesn’t reveal anything about a patient’s overall health, the report says, and doesn’t distinguish between muscle and body fat and doesn’t account for more dangerous fat around the waist and organs.

Experts advocate a new model that looks at the signs of obesity that affect the body’s organs – such as heart disease, shortness of breath, type 2 diabetes or joint pain – and their detrimental impact on everyday life.

This indicates that obesity has become a clinical disease and requires drug treatment.

However, people with “preclinical obesity” should be offered weight-loss advice, counseling and monitoring instead of drugs and surgery to reduce the likelihood of developing health problems. Treatment may also be required.

“Obesity is a health risk – the difference is that for some it is also a disease,” Professor Rubino said.

The rethinking was smart, he added, to understand the level of risk in the larger population, rather than the current “blurry picture of obesity.”

A waist-to-height ratio or direct measurement of body fat, along with a detailed medical history, can provide a much more accurate picture than BMI, the report said.

An expert on childhood obesity, Professor Louise Baur of the University of Sydney, who contributed to the report, said the new approach would allow adults and children with obesity to “receive more appropriate care” while reducing over-diagnosis and unnecessary treatment.

At a time when drugs that reduce body weight by up to 20% are widely prescribed, the report says this “reshaping” of obesity “is all the more urgent” because it “improves the accuracy of diagnosis”.

The Royal College of Physicians said the report laid a strong foundation “for obesity to be treated with the same rigor and compassion as other chronic conditions”.

Differentiating between pre-clinical and clinical obesity would be “an important step forward” and “highlight the need for early detection and intervention”, while ensuring that patients whose health is already seriously affected are properly cared for, the college said.

But there are fears that pressure on health budgets could mean less money for those in the pre-obese category.

Professor Sir Jim Mann, co-director of the Edgar Center for Diabetes and Obesity Research in Otago, New Zealand, said the focus was likely to be “on the needs of those defined as clinically obese” and limited funding was “very serious”. will most likely be aimed at them.