Pioneering new research from the University of Sheffield and the University of Nottingham has found that the waist-to-height ratio (WHtR) is a more accurate and reliable indicator of age-related obesity risk compared to the widely used Body Mass Index (BMI), particularly in older adults. The study, which analysed obesity trends in England between 2005 and 2021 using data from the Health Survey for England, suggests that relying solely on BMI can lead to the under-diagnosis of obesity in older individuals. Researchers highlighted that BMI often fails to differentiate between muscle and fat mass. As people age, muscle mass naturally declines while abdominal fat can increase, leading to a potentially misleading 'normal' BMI despite the presence of dangerous visceral fat. In contrast, WHtR provides a clearer representation of visceral fat, which is stored around internal organs and is strongly linked to serious health conditions such as heart disease, stroke, and dementia. The findings also indicate that unlike BMI, which tends to peak in middle age and then decline, WHtR consistently increases with age, more accurately reflecting the rising health risks in older populations. Dr. Laura Gray, a co-author from the University of Sheffield, emphasized that WHtR is also simpler for individuals to understand and apply, advocating for the straightforward public health message: 'Keep your waist circumference less than half your height.' This research supports existing recommendations from bodies like the National Institute for Health and Care Excellence (NICE) to use WHtR alongside BMI for a more comprehensive health assessment. The study's implications are significant for preventive care, aiming to identify at-risk older adults earlier and improve public health outcomes globally.