BMI Explained — What It Measures, How to Calculate It, and Why It Has Limitations
Body Mass Index (BMI) is one of the most widely used health measurements in the world. Doctors, nurses, public health organisations, insurance companies, and fitness professionals use it daily to screen for weight-related health risks. Yet BMI is also one of the most misunderstood and misapplied measurements in healthcare. This complete guide explains exactly what BMI measures, how to calculate it, what the categories mean, and — critically — what BMI cannot tell you about your health. What is BMI? Body Mass Index is a numerical value calculated from a person’s height and weight. It provides a simple, inexpensive, and non-invasive way to screen for weight categories that may be associated with health risks. BMI was developed in the 1830s by Belgian mathematician Adolphe Quetelet — which is why it was originally called the Quetelet Index — and was adopted by the World Health Organisation as an international standard for classifying weight status in adults. The fundamental premise of ...