Chances are your doctor or a healthcare professional has discussed BMI with you at some point in time. Like many others, you might have walked away feeling puzzled – not only about what BMI exactly means, but also how it relates to your own health.

Let’s break BMI down for you, and discuss why it may not be as important as some think.

What is BMI?

BMI stands for Body Mass Index. It is a simple calculation of weight in relation to height, and is often viewed by the medical community as a quick, inexpensive and non-invasive snapshot of health. It is also frequently used as a screening tool for various medical conditions.

BMI, though, is a term thrown around too freely at times. Some healthcare professionals talk about it without gathering information about your body composition, genetics, eating habits and physical activity – or a more holistic view into your health.

My take: While one’s BMI should never be ignored, it isn’t a comprehensive marker for assessing an individual’s health. Some reasons:

  1. It is outdated:

BMI is an outdated calculation that was developed in the 19th Century by Jacques Quelet, a mathematician, not a physician. First off, why are we accepting health advice by a mathematician? Second, there have been so many advances in medical care since the 1800’s. It doesn’t make much sense to outdate ourselves like this.

  1. It does not account for variance in body mass:

BMI does not take into account the varying forms of mass in the body. BMI cannot tell the difference between muscle, fat, water or bones! It also fails to consider factors which may alter one’s body composition including age, sex and ethnicity. Placing focus on BMI alone can easily lead to an inaccurate portrayal of health. Take Aaron Rodgers, quarterback of the Green Bay Packers, for example. His BMI would technically place him in the “overweight” category. As a professional athlete with high muscle mass, this is not surprising. This does not, however, mean that he necessarily is unhealthy.

  1. It is not a great predictor for overall health:

A recently published study from the International Journal of Obesity illustrated why BMI isn’t an ideal measure of one’s health. Researchers looked at the BMI’s of approximately 40,000 adults and compared them to other markers of health. This study found that HALF of the individuals with a BMI in the “overweight” category were, in fact, metabolically “healthy.” It also found that about one-third of the individuals in the “normal” BMI category were actually considered “unhealthy.”

BMI, alone, is not the be-all-end-all statistic measuring our health, nor should it – or any other number – solely define who we are.

I challenge you to let go of the rigid numbers and begin to shift your focus to nourish your body and mind. Talk with your treatment team to learn how to achieve optimal health while leaving numbers at the door.

Of course, if you need any support, we are here to help.



Ashley Vazquez MS, RD, LDN is the Coordinator of Inpatient and Residential Nutrition Services at Walden Behavioral Care. She specializes in medical nutrition therapy and nutrition support for individuals struggling with eating disorders. Ashley hold’s a Masters degree in nutrition from Boston University. Ashley has been working at Walden Behavioral Care’s eating disorder and psychiatric treatment centers since 2012. She has experience working in various levels of care including intensive outpatient programming, partial hospitalization programming, residential programming, and acute inpatient care.