Research Begins to Question Use of BMI – Body Mass Index

Research Begins to Question Use of BMI - Body Mass Index

Body Mass Index (more commonly known as BMI) has been used by all health professionals and those in health insurance agencies for years to decide whether or not an individual is at an “ideal” weight. According to the index which is calculated by dividing the person’s weight by the square of the person’s height; someone with a BMI of 18.5 to 24.9 is “healthy”, whereas a BMI of 25 to 29.9 is classed as “overweight” and a BMI of 30 or over is categorized as “obese”.

Recently a study was done on 40,420 people and the numbers for BMI just did not correlate exactly with their physical health! This study was published last week in the International Journal of Obesity.

How was BMI used in the past?

BMI has been used by government agencies for years, which establishes standards of practice for health care practitioners. From the very beginning of its use, more than a decade ago, there were questions as to whether or not there were individuals who would not fit into these categories. And, when they did fit into the BMI categories; if they really were deemed unhealthy.

What have we learned about BMI since?

Research that was studied used data from the National Health and Nutrition Examination Survey to analyze the real connection between study participants’ BMI and key signs of health—such as blood pressure, cholesterol levels, glucose and triglyceride levels.

Findings included that 47.2% of the “overweight” individuals studied were, in fact, healthy, as were 29% of those labeled as “obese”.

Conversely, more than 30% of those within the “healthy” weight range were found to be metabolically unhealthy for one or more legitimate medical reason.

Why is this information important to you?

Insurance Premiums:

Across America there are an estimated 54 million Americans with high BMI’s that are in fact healthy. Therefore, these individuals do not have the likelihood of incurring any additional medical expenses and so it would be unfair to charge them with higher insurance premiums. On the other hand, it would also be likely that unhealthy people a normal body weight and therefore, BMI, will not be charged any additional health premiums.

Laws & Public Policy:

Researchers have continued to suggest to all policy makers that they should focus on actual health markers as they come up and can be fully evaluated per person, rather than to guess from the beginning and based only on their BMI number.

What’s a better marker of health?

One other method for assessing body weight is the use of Waist Circumference.

This is a second method of assessing body weight and is particularly sensitive as it is a measure of “visceral” body fat; or that body fat right in our middle. It will be easy to imagine that most of us are never going to be comfortable with this discussion. But if you think about the measurement, you can also somewhat agree to the fact that the middle of our body “is the meeting place” for all of us.

For example, if you measure from head to waist, and you measure from foot to waist, you can start to see that this “middle area” may be the thickest part of our bodies. Therefore, if you or I begin to gain some body mass or our clothes suddenly do not fit, then, we can see more easily that this is a telltale area for all of us.

What’s the best measurement of health?

The BMI chart and the Waist Circumference may be two measures that we want to watch out for while government officials continue to figure out what is relevant and what is not. Besides that, you already know if you are unhealthy or healthy just by the way you feel and the visits to the doctor and doing routine lab work. At the very most, the BMI and the Waist Circumference are only two parameters that you have for decision making. For most of the people I have worked with over the years, most did not agree with the findings and felt that it was just too general.

Both charts are readily available. The following is a copy of both measurements for you to do your own evaluation and maybe, even, do some measurements.

BMI Chart BMI Measurements Waist Circumference


Rita Larsen Registered Dietitian at Elite Sports Clubs

Written by Rita Larsen, RDN, CD; Elite Sports Clubs Nutrition Educator & Diet Counselor

Rita is certified in Positive Psychology, University of Penn; has a BS in Dietetics from Kansas State University; and an Internship and Masters at the Indiana University Medical Center.

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