BMI – Calculator

WHAT IS BMI?

BMI stands for Body Mass Index and it is a quick and calculation to assess a patient’s general heath by measuring your overall weight relative to your height. It is not the most accurate assessment to assess your health, but it has been used to assess risk and monitor weight changes to determine surgery eligibility with respect to Medicare and private health funds (BUPA, Medibank etc).

It is calculated by dividing your weight in kilograms by your height in meters squared.  You can calculate your BMI using this calculator.

In Australia, Medicare and the private health funds use this calculation (amongst other things) to determine your degree of weight loss and therefore your eligibility for weight loss reduction surgery. Unfortunately, this kind of surgery (often called bariatric surgery) is not available in the public health system unless your situation is extreme.

Typically, you would require the loss of 5 BMI points with weight stability for over 6 months. You are also required to have skin integrity issues with the loose skin after your weight loss.

How accurate is it?
It was originally described by a Belgian scientist in the 1800’s yet we still use it today. As you can imagine, it has many limitations. BMI divides the weight by too large a number for short people and too small a number for tall people. So short people are misled into thinking that they are thinner than they are, and tall people are misled into thinking they are fatter. It also makes no distinction between fat and muscle (which is much heavier than fat).

DEXA scanning is a much better way to assess body composition but not everyone has access to this advanced machinery.