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What are BMI and the Waist-to-Height Ratio?

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Calculates the Body Mass Index based on weight and height. This calculation is only suitable for persons over 18 years of age.

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Measure at the narrowest part of the waist between the ribs and hip bones.
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Body Mass Index (BMI)

The Body Mass Index (BMI) indicates the relationship between body weight and height. It is often used to determine whether a person is underweight, normal weight, overweight or obese.

Waist-to-Height Ratio (WHtR)

The Waist-to-Height Ratio (WHtR) is a health indicator that expresses waist circumference relative to height. Unlike the BMI, the WHtR takes the distribution of body fat into account.

BMI categories by age

In older adults (65+), the desirable BMI is higher than for younger people.

WHtR categories

A higher WHtR category indicates that excess fat may have accumulated around the abdomen. Abdominal fat is more strongly associated with health risks than fat stored in other areas of the body.

Important notes

  • The BMI and WHtR are reference values that do not account for individual body composition.
  • For athletes with a high muscle mass, the BMI value can be elevated without indicating a health concern.
  • BMI thresholds may also vary by ethnicity.

Data sources