How Reliable Is The Body Mass Index (BMI) – The True Formula Bariatric Surgeon Auburn Indiana

While the formula for body mass index (BMI) has been around since the mid 19th century, it didn't become popular until the 1970s. Since then, there has been some disagreement over the accuracy and fairness of body mass index in determining the percentage of fat present in the body.

Even the author of the paper that resurrected the formula in 1972, Ancel Keys, warned that it wasn't to be used for individual diagnosis. Rather, it was intended for large population studies. But because it was easy to use and understand, it has become adopted as the standard for determining the percent of body fat in a person's body.

While it still is in wide use today, many medical professionals are using it only as a base indicator, relying on far more accurate tests to determine the actual fitness of the individual. This includes skin fold thickness measurements using calipers, bioelectrical impedance, dual energy x-ray absortiometry (DXA), and underwater weighing.

While BMI and body fat have a strong correlation, the body mass index fails to take into account a lot of important variables, including sex, race, and age. For instance, women tend to have more body fat than men and older people tend to have more body fat than young adults.

The disparity is most noticeable with highly trained athletes. Professional athletes often fall within the range of being obese, not because of body fat but because of increased muscularity. This results in an inaccurate BMI reading, a problem many other physically fit people have.

When determining whether BMI is a reliable indicator or not, it's best to use it as one of several indicators of overall health. For example, the National Heart, Lung, and Body Institute recommends looking at two other indicators: your waist circumference (because abdominal fat is an indicator of possible obesity-related diseases) and the presence of other conditions, such as high blood pressure. Finally, remember that body fat levels are just one factor in determining your overall health and your risk for disease.


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