BMI - Is this a poor indicator of health? It’s one of the most popular tools used in clinical practice and apparently schools are now sending letters home to parents if their child is tracking at a higher percentile (!) But is this a good tool? For those unfamiliar with BMI, it is calculated by dividing your weight (kg) by the square of your height (m). The number given will then fall into a category - Underweight, Normal Weight, Overweight, Obese. The limitations of this app