What is BMI?
The calculation of the BMI is a weight evaluation system, referring to the risk of disease, first proposed by the Belgian scholar Adolphe Quelet (1796-1874).
Through the solution of a formula that requires two known values, height and weight, the calculation of the BMI offers a coefficient to be included in a special evaluation grid that allows you to establish: normal weight, underweight, overweight and obesity (the latter, possibly classified in different severity levels).
What is BMI used for?
Since its invention, the BMI has progressively become a leading diagnostic tool for assessing a person's weight and position relative to the normal one - statistically associated with the lower risk of getting sick with metabolic diseases and more.
However, due to poor precision (it does not take into account the size of the skeleton and musculature) and the application limits it entails (it should not be used for the evaluation of children and elite athletes), today the simple BMI is partially replaced. by more accurate and innovative methods of estimation, but certainly less practical.
The most suitable BMI values, when referring to the metabolic-health aspect, are around 21-22 (22.5 kg / m2 in men and 21 kg / m2 in women). However, in one study, British men were more attracted to female models with a BMI of 20.85; this value, which has no predictive significance on the risk associated with metabolic pathologies and various complications, instead offers a snapshot of the average expectations in terms of "ideal weight" - read the articles dedicated to body image and behavioral disorders food (DCA).
The normal range of BMI (18.5-24.9 kg / m2) is wide precisely as a function of the subjective differences related to the physical structure of the population. As anticipated, the calculation of the BMI does not take into account the muscle mass (greater, for example, in men and young people than in women and the elderly), much less the differences regarding bone mass and the proportion between length of the limbs and stature.
Men and Women
BMI for men and women
Many argue that the BMI must take into account gender, i.e. that it is different between men and women. In reality it is an imprecision, because what makes the difference are characteristics that tend to be linked to it, but not in a direct and linear way.
The BMI does not consider factors such as the extent of muscle mass, skeleton and essential fat. It is well known that men have on average a higher musculature and bone structure than women, that the elderly are weaker than the young, and that women have a higher percentage of essential fat necessary for reproductive function. Regarding the bones, it is possible to integrate the calculation of the BMI with integrative equations that allow to estimate this variable as well.
This does not mean that there are women and elderly people with higher muscle volumes and lower fat mass than most men and young people. This is why the BMI assessment should not be used to estimate a person's weight too precisely and accurately, but simply to identify the risk index associated with overweight and underweight.
The calculation of the BMI is a weight evaluation system, referring to the risk of disease, first proposed by the Belgian scholar Adolphe Quelet (1796-1874).
Through the solution of a formula that requires two known values, height and weight, the calculation of the BMI offers a coefficient to be included in a special evaluation grid that allows you to establish: normal weight, underweight, overweight and obesity (the latter, possibly classified in different severity levels).
What is BMI used for?
Since its invention, the BMI has progressively become a leading diagnostic tool for assessing a person's weight and position relative to the normal one - statistically associated with the lower risk of getting sick with metabolic diseases and more.
However, due to poor precision (it does not take into account the size of the skeleton and musculature) and the application limits it entails (it should not be used for the evaluation of children and elite athletes), today the simple BMI is partially replaced. by more accurate and innovative methods of estimation, but certainly less practical.
The most suitable BMI values, when referring to the metabolic-health aspect, are around 21-22 (22.5 kg / m2 in men and 21 kg / m2 in women). However, in one study, British men were more attracted to female models with a BMI of 20.85; this value, which has no predictive significance on the risk associated with metabolic pathologies and various complications, instead offers a snapshot of the average expectations in terms of "ideal weight" - read the articles dedicated to body image and behavioral disorders food (DCA).
The normal range of BMI (18.5-24.9 kg / m2) is wide precisely as a function of the subjective differences related to the physical structure of the population. As anticipated, the calculation of the BMI does not take into account the muscle mass (greater, for example, in men and young people than in women and the elderly), much less the differences regarding bone mass and the proportion between length of the limbs and stature.
Men and Women
BMI for men and women
Many argue that the BMI must take into account gender, i.e. that it is different between men and women. In reality it is an imprecision, because what makes the difference are characteristics that tend to be linked to it, but not in a direct and linear way.
The BMI does not consider factors such as the extent of muscle mass, skeleton and essential fat. It is well known that men have on average a higher musculature and bone structure than women, that the elderly are weaker than the young, and that women have a higher percentage of essential fat necessary for reproductive function. Regarding the bones, it is possible to integrate the calculation of the BMI with integrative equations that allow to estimate this variable as well.
This does not mean that there are women and elderly people with higher muscle volumes and lower fat mass than most men and young people. This is why the BMI assessment should not be used to estimate a person's weight too precisely and accurately, but simply to identify the risk index associated with overweight and underweight.
Show More