Travis Kelce, Jake Gyllenhaal and why BMI is problematic. It needs to change, panel says.

Was actor Jake Gyllenhaal overweight when he filmed Road House? Should Kansas City Chiefs' tight end Travis Kelce be considered nearly obese?

According to the current definition of "overweight" and "obesity," a ratio of height and weight, both men meet those standards.

But this measure, called body mass index, or BMI, lacks nuance and fails to tell whether a person is truly healthy, a global commission of medical experts said in a paper published Tuesday in The Lancet Diabetes & Endocrinology.

The diagnosis of obesity should include a measure of body size, like waist circumference, and BMI. Another option is measuring body fat, the commission said.

This isn't just a matter of vanity. It could determine who gets access to treatments such as weight-loss medications and who doesn't, several obesity experts told USA TODAY.

Fat and fit?

Not all excess weight is equal, The Lancet commission acknowledges.

The Centers for Disease Control and Prevention defines obesity as a person who has a BMI of 30 or more. As of March 2020, nearly 42% of U.S. adults had obesity, according to the CDC.

Athletes and people who are very fit, like Kelce and Gyllenhaal, may have a higher BMI because muscle typically weighs more than fat. But that doesn't make them unhealthy.

At 6 feet and 184 pounds for the Road House filming (and a reported 5% body fat), Gyllenhaal just met the cutoff for being "overweight," but was definitely not unhealthy. Kelce, at 6 feet, 5 inches and 250 pounds has a BMI of 29.6, just shy of the 30 BMI cutoff for being considered "obese," accoding to the CDC's BMI calculator.

Women's rugby player Ilonah Maher, who has a BMI of 29, told People.com she has been classified as "overweight" since elementary school and the measure is “really not helpful for athletes.”

"Clinical obesity," The Lancet commission said, is a chronic disease that harms a person's organs or limits daily activities such as bathing, dressing, eating or going to the restroom. People with such a diagnosis should get care and possibly treatments such as weight-loss drugs.

A second category, called "pre-clinical obesity," includes people who have a higher BMI and excess body fat but are otherwise healthy. These people might eventually be at risk for obesity-related diseases such as type 2 diabetes, heart disease and some types of cancer.

Researchers said using BMI alone as the sole arbiter of obesity is inadequate and doesn't measure a person's fat distribution around the body.

Some who carry excess fat at the waist or around their liver or heart might face a greater health risk than those with extra fat in the arms or legs, said Robert Eckel, a University of Colorado Anschutz professor and one of more than 50 medical experts who served on the commission.

Will the new definition change medication coverage?

The commission's recommendation comes as doctors and consumers flock to a popular class of weight-loss drugs called glucagon-like peptide 1 (GLP-1) to treat obesity, type 2 diabetes, heart disease and even sleep apnea. But the drugs have side effects and are expensive for consumers, health insurance companies, government insurers and employers who provide health benefits.

Because the weight-loss drugs have been effective but pricey, medical decisionmakers are trying to prioritize who should get these medications, said Justin Ryder, a pediatric obesity researcher and professor at Northwestern Feinberg School of Medicine who was not part of the commission.

"There's been a lot of questions about who should be receiving obesity medications and what are the right criteria to identify patients who should be put at the front of the line for more aggressive treatment," Ryder said. "Where do we sort of draw the line in terms of who has obesity, who should we be monitoring more carefully and who do we not need to worry about so much?"

Ryder said the commission's report provides clarity to doctors and patients and could influence whether health insurers cover weight-loss drugs or other treatments.

Doctors now prescribe Novo Nordisk's weight-loss drug Wegovy for people who have a BMI of 30 or more. Patients who have a BMI of at least 27 can also qualify if they have another weight-related medical condition such as high blood pressure or elevated cholesterol.

Based on the commission's recommendations, health insurers might require people to meet a minimum BMI threshold plus a secondary measure, such as waist size or body fat percentage before paying for the weight loss drugs, Ryder said.

The commission said 18 factors can support a diagnosis of obesity. Examples include breathlessness, high blood pressure, knee or hip pain, reduced range of motion due to excess body fat, heart failure or other organ dysfunction. Children and adolescents with obesity might have limited movement or might trip and fall more often due to bones that aren't aligned correctly.

The commission likely sought to expand weight-loss drug coverage by more precisely defining obesity, but "I'm not so sure that this is going to quite do it," Ryder said.

What do obesity specialists think about the recommendation?

Doctors and medical groups that treat obesity have long advocated a more nuanced approach, rather than solely relying on BMI, said Dr. Angela Fitch, former president of the Obesity Medicine Association.

Obesity should be more than a number, said Fitch, a co-founder and Chief Medical Officer of knownwell, an obesity and primary care provider in the Boston and Dallas areas. It should also have health consequences.

The high cost and limited coverage for obesity medications is driving many people to seek alternative treatments or other options that might not be safe, Fitch said.

"There's a lot of shady stuff happening," she said. "People are being taken advantage of."

What do fat advocates think about the new definition?

Classifying obesity as a disease can harm people who are overweight and reinforce stigma, said Tigress Osborn, executive director of the National Association to Advance Fat Acceptance.

Creating a new category of pre-clinical obesity "still categorizes all the fat people as being pre diseased," Osborn said.

Her organization advocates for tailored treatment for each individual rather than classifying obesity as a disease.

"The idea that stigma is decreased by convincing more and more people to treat fatness as a disease has not borne out," Osborn said.

(This story has been updated to add new information.)

This article originally appeared on USA TODAY: Travis Kelce, Jake Gyllenhaal and why BMI is problematic