The Body Mass Index
(BMI)
is the ratio of the body mass the square of the height in meters.
\begin{equation} bmi = \frac{m}{h^2} \end{equation}
where $m$ is the body mass en $h$ the height of a person.
The BMI is an indication of a person's total body fat and does not measure the body fat directly. It is a moderate correlation with direct measures of body fat. The index can be used as a screening tool for determining whether a person is underweight, has a normal weight, has overweight or is obese.
The BMI classification uses the following guidelines: underweight
(≤18.5)
, healthy weight
(18.5–24.9)
, overweight
(25.0–29.9)
, and obese
(≥30.0)
.