The acronym BMI stands for body mass index.

The body mass index (BMI) is a measurement of overall body fat percentage calculated based on height and weight.  The results are interpreted based on standard weight status categories.

Advantages to Using the Body Mass Index

Experts agree that the body mass index is not a perfect measurement tool.  Though it has its flaws, it is a simple calculation that on average is fairly accurate at indicating an individual's health risks based on weight.  Research has demonstrated that when compared to other more complicated body fat measurement test methods such as the hydrostatic body fat test and dual energy x-ray absorptiometry, it held its own.

Most experts agree that though the BMI is a useful primary indicator of weight issues that may increase health risks, it should not be used as an individual gauge.

Disadvantages to Using the Body Mass Index

Though a useful tool for its ease, there are many pitfalls to using the body mass index scale solely, as a serious health evaluation tool for all individuals.  The first pitfall is that the BMI does not take into consideration muscle mass.  This means that a heavily muscled athlete may have a BMI that places him in the overweight category when in fact he is in prime physical condition.  Take Michael Jordan for example.  In his prime, his BMI was calculated at 27-29, placing him in the overweight category, which was obviously far from the truth.

The second disproportionate factor of the body mass index is that it interprets data for both men and women equally.   Women, on average, have more body fat than men do.  On average, fat comprises 25% of a women's body in contrast to 15% for a man.  Depending on the size, breasts alone can average a few pounds.

Another factor that the BMI does not consider is that individuals with excessive abdominal fat are at a higher risk for health complications than individuals with higher BMI readings with fat about the hips.  Further factors that could create an inaccurate reading are differences in populations, frame size, elderly who have lost muscle, and pregnant women.