The Body Mass Index (BMI) is a simple measure of obesity based on height and weight that applies to both adult men and women.
BMI does not differentiate between body fat and muscle mass. Therefore, body builders and people who have a lot of muscle bulk will have a high BMI but are not actually overweight or obese.
To determine your BMI you need to know your height in centimetres and your weight in kilograms. Use the calculator provided on this page to work out your current BMI.
The higher the BMI the more risk there is to overall health. Additionally, your waist to hip ratio can also be a health risk predictor. Fat predominantly distributed around the waist represents more visceral fat storage (fat stored around the internal organs of your body) which is a much higher risk to health, as opposed to excess fat being stored on the hips, legs and buttocks.
Waist:Hip Ratio Risk
If you are a woman:
- your risk to health is increased at 80cm or more
- your risk to health is greatly increased at 88cm or more
If you are a man:
- your risk to health is increased at 94cm or more
- your risk to health is greatly increased at 102cm or more
Note – To measure your waist:hip ratio your tape measure must be in contact with your skin (not across clothing) and your waist is technically halfway between your lowest rib and the top of your hipbone.