Can Obesity Care Overcome Fixation on BMI?

One of the easy predictions to make for 2023 is that it will be a year of hot debates about obesity. We have plenty of hot topics to choose from, but one of the hottest is what to do with BMI. It is firmly planted in the landscape of discussions about obesity because it can be useful. But in obesity care, BMI can get in the way of a sharper focus on health. At the 63rd Conference of the Spanish Society of Endocrinology and Nutrition, Carel Le Roux explained:

“The definition of obesity of the World Health Organization is the abnormal excess of adipose tissue that leads to a deterioration in health. It is terrible, but it is the best definition that we have today. However, when managing this concept, we must be capable of identifying two distinct entities. On the one hand, the evidence that obesity is a disease. On the other, the cultural desire to be thin.

“The latter, in principle, is not a poor premise, as long as the importance of clearly transmitting to the patient the message that he or she is being treated for a disease is not lost, underscoring that the main objective is not to make them thin only for them to be happier or to look better physically. We have to overcome the idea that our work is to help people lose weight, assuming instead that the obligation of endocrinologists is to treat a disease. As a result of doing so, the patient will lose weight naturally.”

A Socialized Preference for Thinness

Professor Stefanie Johnson tells us that “thin has been in for the last hundred years.” She traces the origin of this beauty standard to the 19th century, when magazines began promoting body images of muscular men and slender women as an aesthetic ideal.

Despite a robust movement toward body positivity and inclusivity, the implicit bias against individuals in larger bodies remains strong.

The Signal That BMI Provides

Bullies and fat shamers don’t need BMI to marginalize people living with obesity. Visual cues are quite enough.

For clinicians and epidemiologists, though, it can be a useful, objective measure of weight for height. It does a decent though imperfect job of predicting health risks. For obesity care, BMI can be a simple screening tool and one marker for clinical progress.

But weight loss or BMI reduction is not the whole point of obesity care. The point is to reduce the harm that obesity does to a person’s health and quality of life. That will require overcoming the fixation on BMI without discarding it altogether.

Click here for more perspective from Le Roux and the discussion on re-thinking BMI. For further perspective on the use and misuse of BMI, click here. Finally, this article from Salon offers historical perspective on the social preference for thinness.

Girl in a Sailor’s Blouse, painting by Amedeo Modigliani / WikiArt

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January 5, 2023