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Checking your body mass index

If you are worried about being overweight, healthy eating and being physically active is the best way to bring it down and keep it down sensibly.

You can check whether you are a healthy weight by working out your body mass index (BMI). You do this by taking your weight (in kilograms) and dividing it by your height (in metres) squared. So, if you weigh 65 kilograms and are 1.73 metres tall, you would have a BMI of 65 (1.73 x 1.73) = 21.7.

Under 18.5 is considered underweight, over 25 is considered overweight, and over 30 is obese.

A BMI of below 18.5 is undesirable and you may need a healthier diet with regular meals and exercise. It might be worth having a health check with your GP to help you make the changes you need.

Although useful for most people, BMI isn't useful for everyone. It's not suitable for young children, or older people. It's also not very useful if you're athletic, physically active, and have naturally high muscle bulk. The heavier muscles will push up your BMI measurement.

• BMI calculator Opens new window

Healthy diet

Fruit and vegetables are generally low fat, low calorie foods. So eating fruit and vegetables instead of foods that are high in fat and added sugars may help you achieve, or keep to, a healthy weight.

A healthy diet contains:

• plenty of starchy foods like bread, rice, pasta, breakfast cereals, potatoes, yams and sweet potatoes - look for higher fibre versions where possible (like wholemeal bread or pasta)
• at least five portions of a variety of fruit and vegetables daily
• moderate amounts of dairy products (or alternatives) - look for low fat versions where possible
• moderate amount of meat, fish or alternatives like eggs, beans, peas and lentils - look for lower fat versions where possible
• the occasional treat (foods that are higher in fat, salt or added sugar should only be eaten in moderation)
• little salt - always read the label

• Healthy eating

Physical activity

Find ways of increasing your activity which are realistic for you. This doesn't have to mean going to the gym or taking up sport – many people find it suits them better to go for a regular walk or join a dance class.

As an adult you should aim to be active on five or more days of the week:

• 30 minutes of activity will have general health benefits and improve your fitness
• increase activity to at least 60 minutes to help you lose weight and stop weight going back on  

• Sports facilities and events

More useful links

• Health weight information from the Food Standards Agency Opens new window
• 5 A DAY fruit and vegetable website Opens new window
• British Heart Foundation - Keeping your heart healthy Opens new window
• The British Heart Foundation's National Centre for physical activity and health Opens new window
• Sport England Opens new window