Are you obese or overweight?

Body mass index

Your body mass index (BMI) is a good estimate of how much of your body is made up of fat. It relates your weight to your height. You can work out your BMI by dividing your weight (in kilograms) by the square of your height (in metres).
So, for example, if you weigh 70 kg and are 1.75 metres tall, your BMI is 70 / 1.75 x 1.75, which is 22.9. Alternatively, your practice nurse can measure and weigh you, and tell you your BMI.

BMI	Classed As	Health Risk
Less than 18.5	Underweight	Some health risk
18.5 to 24.9	Ideal	Normal
25 to 29.9	Overweight	Moderate health risk
30 to 39.9	Obese	High health risk
40 and over	Very obese	Very high health risk

Waist size

Your increased health risk is greater when the extra fat is mainly around your waist ('apple shaped'), rather than mainly on your hips and thighs ('pear shaped'). As a rule, a waist measurement of 102 cm or above for men (92 cm for Asian men) and 88 cm or above for women (78 cm for Asian women) is a significant health risk.

In short, the heavier you are, the longer your carry the extra weight, and the more the fat is around your waist, the greater your health risk.

How common is obesity and overweight?

More than half the adults in the UK are heavier than recommended. About 2 in 5 adults are overweight, and about a further 1 in 5 are obese. The number of obese people in the UK is rising, particularly among young adults. Since 1980, the number of obese adults in the UK has nearly tripled. This has been called the 'obesity epidemic'.