In Canada, obesity will no longer be determined by weight alone

The physicians, who are part of the non-profit Obesity Canada and the Canadian Association of Bariatric Physicians and Surgeons, believe doctors have not been treating patients with obesity the way they should be. In their view, weight discrimination impedes treatment and medicine has made little room for body positivity.

Obesity, they argue, should be defined by a person's health, rather than just their weight.

The guidelines, which were published this week in the Canadian Medical Association Journal, reccomend that obesity be classified as a chronic illness that requires tailored treatment and long-term care.

The authors also encourage doctors to stop relying on BMI (or body mass index) alone when it comes to diagnosing their patients.

By that definition, people would only be diagnosed as obese if their body weight affects their physical health or mental wellbeing, said Dr. Arya Sharma, professor of medicine at the University of Alberta, Edmonton, and scientific director of Obesity Canada, who co-wrote the guidelines.

"This is a huge departure from this notion that you can step on a scale and diagnose obesity," Sharma said. "This has nothing to do with size or shape or anything else. It's simply the question, is your body fat impairing your health?"

Five steps to better obesity treatment

The new guidelines provide a five-step road map for doctors to follow when treating patients with obesity.

The first step -- an approach Sharma joked was "very Canadian" -- encourages doctors to ask their patients whether they feel comfortable discussing their weight. If they are, and they want to pursue treatment, then doctors can move forward.

In this stage, doctors should also learn to reconsider obesity not as a personal failure, but as a chronic illness that isn't curable with a temporary diet or even a major procedure like bariatric surgery. As a result, it requires long-term care from a physician.

"Obesity management has to be based on the principles or chronic disease management, which means any quick fix ... none of that is going to have a long-term impact," Sharma told CNN.

Obesity is considered a serious condition that occurs when a patient has a dangerous amount of excess weight. About 30% of Canadian adults have obesity, according to Obesity Canada, while the number rises to over 42% among Americans.

It's linked to severe conditions like heart disease, cancer and sleep disorders, according to the National Institutes of Health. But obesity is a complex condition of its own, one that can be caused by genetic, psychological or environmental factors, among others, Sharma said.

It's a physician's duty to identify those causal factors in their patient, chart a course for tailored treatment and cooperate with the patient along the way, he said -- steps two through four of the recommendations.

Not all treatment options for patients with obesity involve losing weight, Sharma said -- if a patient eats healthier foods, exercises often and is showing overall signs of improved health without losing weight, then they're succeeding.

"I don't care what's going on on the scale," he said. "The real question is, does my patient feel better? The problems related to obesity -- are those conditions now better controlled? That may or may not take weight loss."

The fifth step involves assisting patients with barriers to meeting their goals, whatever they may be. It's a doctor's job to be supportive and identify those barriers before they come up so they don't stifle a patient's success, per the new guidelines.

Medicine's tricky treatment of weight

Weight has become a polarizing and knotty topic in medicine.

The stigma of obesity has impeded existing treatment, the team of Canadian doctors writes in their guidelines. Doctors may write off patients with obesity as lacking in willpower or irresponsible, Sharma said, or may even bring up their weight when it's not pertinent. The biased treatment is enough to drive people with obesity away from medicine for good, he said.

These guidelines are an "excellent upgrade" from the former approach to obesity, said Sylvia Ley, an assistant professor in the department of epidemiology at Tulane University who was not involved with the study.

"The new guideline attempts to address obesity as a complex disease to be managed using a combination approach ...," Ley wrote to CNN in an email. "It also recognizes the importance of patient-centered, individually tailored approaches."

But the guidelines aren't perfectly aligned with the fat acceptance movement, though Sharma said the guidelines were created with the cooperation and input of people with obesity. Many fat-positive activists reject the belief that fatness is a disease or a defect.

Ali Thompson, a writer, YouTuber and fat activist, told CNN that characterizing fatness as a disease "turns a normal human variation into a problem that has to be solved."

The guidelines could also still leave room for discrimination among doctors, Thompson said.

"Any standard of care for fat people that doesn't begin and end with 'treat them like thin people' is inadequate," she said.

She also disagrees with calling obesity an "epidemic," as the US Centers for Disease Control and Prevention and National Institutes of Health have.

"It's extremely dehumanizing to be talked about in the same way as a virus," she said.

Public health researchers and fat acceptance advocates may disagree when it comes to obesity, how to describe it and whether it requires medical intervention. But Sharma said the guidelines aren't designed to force people into accepting treatment. If someone isn't interested in changing anything about themselves, then they shouldn't be made to as long as their health isn't in jeopardy, he said.

"Before, we had one recommendation: Eat less, move more," Sharma said. But that was just one narrow view of a complicated condition of which there's no one root cause.

The guidelines, Sharma and his colleagues hope, open a window for a more sympathetic view of obesity, one that centers around patients.