Adolphe Quetelet, a Belgian mathematician born in 1796, invented the BMI formula. It was then and still is now the favorite and flawed tool to measure a person healthy weight. Based on the formula, myself, Arnold Schwarzenegger, Mel Gibson, and Sylvester Stallone are all obese. Yes, you read it right, obese. The formula claims to measure a person’s healthy weight by dividing their height by their weight. This formula calculates what’s called your BMI (Body Mass Index) score and then measured on a chart that classifies you as underweight, normal overweight or obese.

Here’s the so-called Body Mass Index formula:

Height in centimeters ÷ Weight in kilograms = BMI

The BMI Chart is flawed because it doesn’t consider muscle mass

Instead, the formula calculates a percentage of your body weight, which could be fat or muscle. And while excess body fat mass can show obesity and a slow metabolism, in comparison lean muscle mass is an indicator of good health and a faster metabolism. Since both muscle mass and fat weigh about the same, there’s no way for the chart to differentiate between the two. A high BMI doesn’t mean you’re overweight or have excess body fat. For example, let’s take Arnold’s weight, at his Mr. Universe shape (did he look obese to you?), which is 235 lbs. and 6’2″ tall and had a 7% fat percentage, he is still classified on the chart as obese according to the BMI chart.

There are better ways to determine a person’s healthy weight. One of my favorites is your waistline, it tells you everything. And as I tell my clients, it’s always best to get a clear picture of your body composition, rather than trusting a number that makes a rather vague statement about one’s health.