top of page
  • Writer's pictureBarbara J. Mayfield, MS, RDN, LD, FAND

Obesity is misunderstood and BMI is misused. How can we provide clarity?

tape measure, BMI charts, medicines

A nutrition topic that has gone through a major transformation in recent years is our understanding of the disease of obesity.

When I was a nutrition student and then a young dietitian the thought was that overweight and obesity were caused by eating too much, moving too little, or a combination of both.

The message was basically “Eat less and move more.” We believed that it was all about the calories and that creating a deficit would lead to weight loss.

Although we considered potential genetic and environmental influences on obesity back then, the main responsibility fell squarely on the shoulders of those afflicted. What a burden!

The more we learned, the more we realized how little we knew.

Over time, as the numbers of people joining the overweight and obese population steadily grew, we were charged with digging deeper to understand why.

The numbers didn’t add up. The research didn't support the belief that excess weight could simply be explained by caloric differences in intake or expenditure. Calories were part of the story, but only a part. A greater understanding of the physiology of obesity turned this traditional thinking on its head.

The more we learned about the complexity of causal influences on weight gain, the more we were forced to question our approaches to assessment, prevention, and treatment. It forced us to rethink what was to blame and to stop dumping shame on the people carrying extra pounds.

A movement took hold to correct misunderstandings.

Over the past decade or two, new thinking surrounding obesity has gradually made a difference within the medical community and in the broader society. Several key areas of note include:

  • Recognizing obesity is a disease with a complex etiology and is not a moral failing.

  • Getting rid of one-size-fits-all treatment and prevention plans.

  • Expressing compassion and understanding for those with the disease.

The following organizations and initiatives have been at the forefront of this movement:

BMI was not intended for diagnosing obesity but was used for it.

Along with recognizing obesity as a disease has come a recognition that BMI, which stands for body mass index, has often been misused as a diagnostic tool rather than the screening tool it was designed to be, which was for assessing overweight and obesity in population groups.

BMI simply expresses the relationship between our weight and our height. It does not measure how much of our weight is fat versus lean tissue or how it is distributed. At the individual level, BMI is a poor predictor of health, especially for racial and ethnic groups not represented in its formulation. More accurate tools are being developed.

A previous post describes a visual aid I’ve used to demonstrate the shortcomings of BMI. You are welcome to use it. And another provides 5 tips for communicating science. When we communicate with clarity we can help change misconceptions about health and nutrition, including obesity.

New messaging brings clarity to the complexity of obesity.

How can we communicate more clearly about obesity? Does its complexity prevent clarity? No.

Audiences don’t have to be able to list every potential contributing factor to understand that a person’s genetics play a major role in causing excess fat accumulation, with environmental and behavioral influences contributing multiple factors, which in turn have an effect on one’s physiology.

Personal responsibility for eating healthfully and being physically active makes a difference, but very often cannot be used to prevent or treat obesity without additional interventions. Finding an obesity specialist or team of specialists who can tailor a plan to the individual is key.

Obesity is a chronic lifelong condition that requires ongoing treatment, not a fad diet or magical cure. New treatments are making a huge difference and offer hope. The challenge is creating awareness, understanding, and accessibility for those who can benefit.

“Obesity is a complex, multifactorial disease that develops from the interaction between genotype and the environment. Our understanding of how and why obesity occurs is incomplete; however, it involves the integration of social, behavioral, cultural, and physiologic, metabolic, and genetic factors.” ~ The National Heart, Lung, and Blood Institute “Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity”

If you like this content, please share:


Rated 0 out of 5 stars.
No ratings yet

Add a rating
bottom of page