Have you ever calculated your BMI and been given a reading of ‘overweight’, when you clearly aren’t? Or maybe you’ve been training hard in the gym but your BMI has increased?
Many of us, including GPs and fitness instructors, use BMI as an indicator of whether we are ‘fit and healthy’ and reliably use it to adjust our lifestyle. However, mathematician Nick Trefethen, Professor of Numerical Analysis at Oxford University, has proposed that the formula is poorly defined and has proposed an alternative.
He claims that the BMI formula, which is calculated as weight in kilograms divided by the square of the height in meters, is an ill-founded definition of body size, and isn’t a useful measure.