Obesity Is Bigger Than BMI

BMI is one indicator of obesity, but other markers also need to be taken into account.

I have a friend who has dignosed himself as “borderline obese” based on his BMI. I look at him and see a thriving person who eats well and likes to lift. The fact that his classification is technically correct is the result of an inadequate definition.

The Journal of the American Osteopathic Association recently addressed this topic. The authors discussed some additional markers that should be used to diagnose obesity and predict its related health concerns. They acknowledged that while BMI might be one indicator of unhealthy body fat levels, other markers also need to be taken into account for a more accurate diagnosis and effective treatment.

BMI has a few benefits for classifying the level of obesity in clients. It’s a decent indicator of healthy weight, and often correlates with body fat. However, BMI doesn’t distinguish between lean muscle mass and fat mass, often to the detriment of perfectly healthy people. On the one hand, you have the “obese” who are athletic and healthy. On the other hand, you have those with a “normal” BMI who suffer from loss of muscle mass due to aging, or the dreaded “skinny fat” people who are at risk despite a healthy appearance.

The problem is simple: healthcare professionals need more dependable data in order to make the most accurate judgment.

Eight women with the same BMI of 30, but different weight distribution and abdominal volume. (Photo courtesy Wikimedia Commons)

A Holistic View of Obesity

The researchers emphasized the need to consider waist circumference in addition to BMI to determine obesity risk. As they noted:

The rationale for measuring the waist circumference in clinical practice is to identify metabolically obese and overweight patients whose BMI is normal and thus would not be considered for lifestyle intervention and treatment.

In other words, adding in this additional criterion for obesity will help identify those clients whose BMI falls on the lower side of the obese or overweight spectrum, but who are still at risk for obesity-related concerns. Waist circumference is a dependable predictor for intra-abdominal fat, which is a major contributor to metabolic syndrome and inflammation.

The researchers also acknowledged the need to consider ethnicity when diagnosing obesity. For example, studies on Asian populations have suggested, “Asians, in general, have a higher percentage of body fat compared with whites of the same age, sex, and BMI.” This puts them at risk for obesity-related health concerns at a much lower BMI than non-Asian populations.

Although waist circumference and ethnicity are often factored into obesity diagnosis in a medical setting, fitness professionals and exercise enthusiasts may not account for these additional warning signs. Before you assume you’ve been spared from the obesity epidemic, you need to consider all the markers that put you at higher risk.

On the flip side, if your BMI has you concerned about your health despite the fact that you feel totally healthy, remember that it’s just one marker for obesity. If your diet, fitness, and stress management are dialed in, you might not need to be scared of the numbers. As this article reminds us, the obesity puzzle is multi-faceted and highly individual.