Are you overweight or obese?

Clinically, obesity can be defined in terms of a number called the BODY MASS INDEX or BMI. To calculate your own BMI, measure your weight (in kilogrammes) and your height (in metres). Then divide your weight by the square of your height as shown in the example below, and read off your BMI from the table, i.e.:

BMI = Weight (in kilos) ÷ height2 (in metres)
e.g. A person weighs 78kg and is 1.6 metres tall, then the BMI is 78 ÷ 1.62 = 30.4. From the table below, it is evident that this person is on the borderline between overweight and becoming clinically obese.

BMI and relative risk of diabetes
less than 20 –underweight/very low risk
20 to 25 – ideal/very low risk
25-30 – overweight/significant risk
above 30 – clinically obese/high risk
above 40 – extremely obese/very high risk