Body mass index: are you the right weight for your height?

For many people, stepping onto the scales is part of their morning routine. Have I gained or lost any weight? How far away am I from my ideal weight, and what even is that? The body mass index (BMI) is often used as a guide.

BMI measures the ratio between your weight and height and is used to assess whether someone is underweight, at a normal weight or overweight. It is calculated using age, height and weight. A person's weight in kilograms is divided by the square of their height in metres, giving a value that can be assigned to a category, taking age into consideration.

Each range can reflect different health risks. A BMI of between 18.5 and 24.9 is classed as normal weight. You can calculate your BMI on the Gesundheitsförderung Schweiz (Health Promotion Switzerland) website.

Too much belly fat is unhealthy

As BMI tells us nothing about body fat, it cannot be used to assess visceral belly fat either. This builds up in the abdominal cavity and surrounds the organs. Excessive visceral fat is not healthy and increases the risk of cardiovascular disease.

To quickly assess whether you have too much belly fat, simply measure your waist circumference at navel height. If it is more than 80 centimetres for a woman or more than 94 centimetres for a man, it would be beneficial to lose a bit of weight, or at least ensure that your waist doesn't get any bigger.

If your waist circumference is 88 centimetres or more for a woman, or 102 centimetres or more for a man, you should regard this as a warning sign. You should try to bring down your waist circumference by a few centimetres, as even this small change can significantly reduce the risk of developing secondary conditions.

Analysing body composition