Definition
Overweight is defined as an augmentation of the body fat. In his severe form it is classified as obesity. Due to the complexity of a direct measurement of the body composition, generally an assessment of the nutritional status is made by using the Body-Mass-Index (BMI) which can be calculated upon body weight and height.
Weight classification of adults based on criteria of the WHO, 1997
| Weight classification | BMI (kg/m2) |
|---|---|
| Underweight | <18,5 |
| Normal | 18,5-24,9 |
| Overweight | 25,0-29,9 |
| Obesity I | 30,0-34,9 |
| Obesity II | 35,0-39,9 |
| Obesity III | ≥40 |
A BMI over 25 kg/m2 is classified as overweight.A BMI over 30 kg/m2 is classified as obesity with grades from I to III and entails serious health risks. A BMI over 40 kg/m2 is classified as morbid obesity. This is a serious condition and can be life threatening. The classification is based on scientific data indicating the risk for different diseases and substantially, precocious death rises with increased overweight.
However, it is also important to acknowledge that a high BMI is not always associated with a high body fat mass, as overweight can also result from a high muscle mass. Therefore, it is necessary to carefully evaluate each patient individually before recommendations on weight loss or other health-promoting measures can be offered.