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What is your Body Mass Index?

Health professionals use a measurement called Body Mass Index (BMI) to indicate if someone is underweight, normal weight, overweight or obese.

BMI is an objective scientific measure that uses your height and weight. You can calculate your BMI by dividing your weight in kilograms by the square of your height in meters (BMI = kg/m2), or simply use the handy BMI Calculators provided below.

Because weight and health are so closely linked, the BMI measures whether you are the best weight for your height.

A BMI over 25 is classed as overweight, and a BMI over 30 is classed as very overweight (or Obese).These cut-off points are based on associations between chronic disease and mortality and have been adopted for use internationally by the World Health Organisation.

BMI Calculators

NHS Choices

BBC Health

NOTE - BMI is not the same as Body Fat!

Two people can have the same BMI, but a different body fat percentage. For example, a bodybuilder with a large muscle mass and a low body fat may have the same BMI as a person who has more body fat - because BMI is calculated using weight and height only.

BMI should only be a guide and this is a good reminder that BMI is not the only indicator of someone’s health risk! BMI is just one of many factors related to developing chronic diseases such as heart disease, cancer, or diabetes. Other factors that may be important to look at when assessing your risk for chronic disease include:

Need to lose weight?

ADVICE: If you have any concerns about your weight contact your GP.

REMEMBER: If you need to lower your BMI do it gradually overtime, don't starve yourself or over-exert your body with strenuous exercise.

TIP: You can experiment with the BMI calculator to see how much weight you need to lose to get your BMI down.

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