Does excess muscle ruin your BMI score?

The BMI, or the Body Mass Index, is a test used by doctors to help patients figure out if they are a healthy weight. The test itself places people in four categories, those of which being underweight, normal, overweight and obese, and is regularly a part of any health examination. Though the test, created by Adolph Quetelet, is over 150 years old, its simple formula of weight (in kilograms) divided by height (in meters) has been the standard since its inception. Is it time to devise a new method to track a person’s health?

One of the arguments against the BMI is that it doesn't take into account muscle mass. Though the mass majority of people don’t carry the type of muscle that weightlifters and other elite athletes do, it still is facet of the test that remains an issue. According to the BBC, a professor of Numerical Analysis at Oxford University, Nick Trefethen, thinks he has come up with a better solution.

According to Trefethen, the equation should be changed to 1.3 x weight, divided by height to the power of 2.5. In regards to the seemingly arbitrary numbers, Trefethen says, “[They] can’t be explained simply. People do scaling arguments to explain as an animal gets longer how, if its bones aren't to break, how much thicker they need to be and out of this kind of mathematical analysis come some rather complicated and unexpected results.” His theory remains unproven.

Tim Cole, a Professor of Medical Statistics at University College London, is not moved by Trefethen’s results. Of this new formula, Cole says Trefethen is, “…aware of the deficiencies of BMI but I don’t think his index goes anywhere to addressing those shortcomings.” He goes on to state the merits of the BMI, in regards to populations, is the reason the test has been around for so long.

Though the BMI isn't a perfect test, there are some merits to its findings. Though by no means are the results an end all be all, a good look at one’s BMI can be a great indicator for evaluating health choices. 

Photo courtesy of www.howstuffworks.com