What does BMI (Body Mass Index) mean?
BMI History
Body mass index was first developed by the Belgian, Adolphe Quetelet, about 200 years ago. It used to be used to describe normal growth patterns, but has since become a tool to assess chronic disease risk.
BMI is calculated by dividing your height by your weight squared
kg/m2 or 703 x lb/in2
The idea is that 1) higher BMI means 2) more body fat which means 3) greater chance of disease
But recent studies have cast doubt on the usefulness of this tool.
Calculate your BMI
What is your BMI classification?
But, does BMI actually predict chronic disease risk?
The main problem with BMI is that it only measures height and weight. What appears to actually affect health is abdominal obesity (visceral fat). So if someone is heavier because of dense bones, or a lot of muscle or subcutaneous fat around the hips, the BMI goes up, but their risk of disease isn't really higher.
One recent study showed that BMI is oftentimes inaccurate when used as a measure of abdominal obesity.
A better method
Waist circumference is likely a better predictor of chronic disease risk than BMI. However, only 1/2 of primary care physicians ever measure WC, and it is often done incorrectly.
How to measure Waist Circumference
Tape measure
You can buy a tape measure on Amazon for less than $3.