Forget the bathroom scales and complex calculations. A simple tape measure could be the key to a more accurate assessment of your health, according to new research. A study has concluded that the waist-to-height ratio is a 'much better indicator' of health than the widely used Body Mass Index (BMI).
The Problem with BMI
The research, led by academics from the University of Sheffield and the University of Nottingham, highlights the long-standing flaws in relying on BMI. The BMI metric, calculated by dividing weight in kilograms by height in metres squared, fails to distinguish between fat and muscle. This means a very muscular athlete can be classified as obese, while an older person losing muscle mass might have a deceptively healthy BMI despite carrying excess fat.
Dr Laura Gray from the University of Sheffield explained the issue. "Quite often we'll hear that athletes have a BMI over 30 and would be classed as living with obesity, but we know that they're not," she said. "Older people tend to lose muscle when they age... their body fat percentage is actually higher, but their weight is still dropping, so BMI starts coming down, but actually they're getting less healthy."
Why the Tape Measure Wins
The alternative, the waist-to-height ratio, is both simpler and more insightful. The rule is straightforward: your waist circumference should be less than half your height. This measurement is particularly effective at estimating levels of visceral fat – the dangerous fat stored around vital organs like the heart and liver, which significantly increases the risk of heart disease and stroke.
"Waist-to-height ratio, because it measures round your waist, is giving us a more accurate measurement of visceral fat," Dr Gray stated. "And visceral fat has 'more of an effect on how things work within your body'." She also championed the method's practicality, noting, "A tape measure is actually cheaper than a set of weighing scales. It's probably easier because it's just a ratio."
The Scale of the Issue
The findings are especially pertinent given England's obesity statistics. In the 2023-24 period, an estimated 64.5 per cent of adults in England were overweight or obese, with 26.5 per cent classed as living with obesity. The study, published in the International Journal of Obesity and based on data from the Health Survey for England (2005-2021), also found that a person's environment has a 'significant influence' on obesity levels.
This research provides a compelling case for both medical professionals and the public to adopt a more nuanced tool for health assessment. Moving beyond the limitations of BMI to a simple waist check could lead to earlier identification of health risks and more targeted advice for maintaining wellbeing.
