A lower BMI threshold of ≥27kg/m² may better identify obesity in patients over 40 than the accepted cut-off of ≥30kg/m², Italian researchers have argued at the 2024 European Congress on Obesity.

They said changes in body composition with ageing — namely, increased body fat and decreased lean mass — meant the current one-size-fits-all cut-off of ≥30kg/m² could underestimate obesity rates.

“If we continue to use the WHO standard for obesity screening, we will miss many middle-aged and older adults who are at risk for obesity-related diseases, including type 2 diabetes, heart disease and some cancers,” said Professor Antonino De Lorenzo from the Tor Vergata University of Rome.

For their single-centre study, which is yet to be published in a peer-reviewed journal, the team assessed more than 4500 patients’ adiposity based on their total body fat percentage (BF%) measured with dual-energy X-ray absorptiometry and using age and gender-specific cut-offs for obesity based on BF%.