BMI - should I use it?

The Body Mass Index (BMI) was developed by a Belgian astronomer, Adolphe Quetelet in the mid 1900’s. 

His formula divided a persons weight by their height to give a score "BMI". Although not entirely satisfactory, it has been considered as good as any other indicator of relative obesity. 

  • Anything under 18.5 is considered underweight
  • 18.5 - 24.9 is considered a healthy weight
  • 25-29.9 is considered overweight
  • Anything over 30 is considered obese. 
The simplicity of BMI is its downfall. It takes no account of age or gender, the scoring system was devised for a different age and takes no account of changes in nutrition over the last 200 years. Most fitness models and athletes fail the BMI test because of the amount of muscle mass not fat on their bodies. In fact it makes no distinction between fat and muscle at all. 

So why use it? Well the short answer here is don’t. Focus on measuring your body fat, it is the only true way to measure healthy body composition and there are million tools and apps available to help you. My advice, leave it in the 1900’s along with gas lighting and the horse drawn carriage.