To begin with, let us note that the Body Mass Index or “BMI” which was adopted by the WHO is a handy tool that provides us a rough idea of the adaptability of our weight vis-à-vis our height; this means, if we are thin, overweight, or obese. In order to calculate our BMI, we have to divide our weight (kg) by our squared height (m) (for example, a person who weighs 70 kg and whose height is 1.78 m will have a BMI of around 22.1). You will find at the end of this article some brief details on the meaning of various BMI values. Also, we should note that this formula is primarily intended for healthy adults.
Furthermore, the BMI is an indicator that should be used with caution. It can be interpreted differently depending on every person’s situation and physical traits: pregnant or lactating lady, elderly person, child and teenager, sick person, hard athlete, especially muscular sportsman, giant or dwarf, etc. In addition, the BMI does not account for the muscle mass, the bone structure and fat distribution. Also, dehydration can decrease BMI while edema or high water retention can increase it.
Finally, you should make sure to have the results of your BMI complemented by a nutritional assessment or clinical examination to be performed by a specialist person.
Below is a brief interpretation of the various results of the BMI:
Underweight – BMI < 18.5
Normal – 18.5 < BMI < 24.9
Overweight – 25 < BMI < 29.9
Moderate obesity – 30 < BMI < 34.9
Severe obesity – 35 < BMI < 39.9
Massive obesity – BMI > 40