Why BMI is Inaccurate and Misleading
Wrestler Steve Austin, at the height of his career weighed 114kg (252lbs). He was 6ft 2ins tall. His BMI at 32.4 would class him as obese
BMI (body mass index), which is based on the height and weight of a person, is an inaccurate measure of body fat content and does not take into account muscle mass, bone density, overall body composition, and racial and sex differences, say researchers from the Perelman School of Medicine, University of Pennsylvania.
Every few months the same comment is made by experts “BMI is flawed”. The news hits the headlines, everybody agrees, and then all goes quiet for a while.
You are of normal weight if your BMI is between 18.5 and 25, overweight if it is between 25 and 30. Anybody with a BMI of 30 or more is obese.
Mitchell Lazar, MD, PhD, Professor of Medicine and Genetics and Director of the Institute of Diabetes, Obesity, and Metabolism, and Rexford Ahima, MD, PhD, Professor of Medicine and Director of the Obesity Unit in the Institute for Diabetes, Obesity and Metabolism, discuss the challenges health professionals face when studying the mortality risks and health of obese people in the journal Science1.
We all know that obesity increases the risk of developing heart diseases, type 2 diabetes, cancer, sleep apnea and other diseases and conditions.
However, according to recent studies, obesity may also protect against death from all causes, as well as death due to stroke, heart failure and diabetes.
In the Science article – “The Health Risk of Obesity – Better Metrics Imperative”2 – the authors refer to the pros-and-cons of obesity as the “obesity-mortality paradox”. A paradox that generates a great deal of controversy.