The body mass index (BMI), or Quetelet index, is a measure of relative size based on the mass and height of an individual.
The index was devised by during the course of developing what he called “social physics”, between 1830 and 1850. The BMI for a person is defined as their body mass divided by the square of their height—with the value universally being given in kg/m2.
The BMI of an individual may also be determined using a table or chart which displays BMI as a function of mass and height using contour lines or colors for different BMI categories, and may use two different units of measurement.
There are a wide variety of contexts where the BMI of an individual can be used as a simple method to assess how much the recorded body weight departs from what is healthy or desirable for a person of that height. There is, however, some debate about which values on the BMI scale the thresholds for underweight, overweight and obese should be set.
Department of Surgery 