The body mass index (BMI – Body Mass Index) is, as the name implies, an index that gives us approximate information on the level of fat of an individual and therefore his health state. It is also used to get information on the risks related to the diseases that an individual may incur. Among the various diseases, we find diabetes 2, high blood pressure, heart problems, heart attack, kidney and liver diseases, etc.
The body mass index (BMI – Body Mass Index) is calculated taking into account only 2 data: the weight and height of the individual.
The result obtained is compared with a table that classifies the individual as underweight, normal weight, obese of grade 1, obese of grade 2, obese of grade 3.
You can calculate your body mass index (BMI – Body Mass Index) with our automatic calculator that you find below and compare it with the relative table.
Advantages and limitations of BMI
Among the advantages of the Body Mass Index (BMI) are ease and speed in practice, and it is preferably used to draw conclusions on the greeting status of a given population, and therefore, on a large number of individuals.
Its biggest limitation lies in the INDIRECT APPROXIMATION of the percentage of fat mass (read more: percentage of fat mass) of a given individual. What does this mean? It means that the result obtained by comparing the BMI value with the table (underweight, normal weight, obese grade I, etc.) does NOT truthfully reflect the individual’s condition, but approximates it.
A subject with particular body composition (read more: body composition) characterized for example by a high amount of muscle mass and a low percentage of fat, could also be classified as obese, this because the body mass index goes to estimate the fat of a subject knowing the only height and weight.
So why is BMI used? Because it is a fast and easy-to-use tool, which on a general population gives a good estimate of the health status of the subjects examined.
For particular subjects, such as sportsmen, the use of tools that estimate the percentage of fat mass rather than the use of the body mass index is more appropriate (read more: how to calculate your body composition).
Examples of BMI and different body composition
Here are some examples of subjects with the same height, the same weight and therefore the same body mass index, but with completely different body composition.
The body mass index can be used to have an ESTIMATE of the state of health, more suitable for subjects in the average population.