Until she was in her mid-30s, Xanthia Walker rarely went to the doctor, even when she needed care. She didn’t want to step on the scale.

When she did go in — to treat sciatic nerve pain or get antibiotics — somehow the conversation always turned to her weight.

“Even when I went in about migraines, the response was, ‘Well, if you lost weight that would probably go away,’” she recalled.

That changed when Walker, 40, who lives in Phoenix, found a new physician. Dr. Natasha Bhuyan rejects what she calls the “weight-centric” model of medicine.

Instead, she favors a “weight-inclusive” approach recognizing that people come in different shapes and sizes, and that the number on the scale does not necessarily predict health status.

“When a person comes in, the first thing we do is not check their weight,” said Bhuyan, who is the vice president of in-office care and national medical director at One Medical, a primary care practice owned by Amazon.

“We bring them back, sit in the exam room, and just talk with them,” she said. “It’s a paradigm shift — if we do feel we need to check their weight, we get their permission.”

That approach is still controversial for many doctors. Medical school students are taught that a patient’s weight is one of the vital signs that should be checked at each medical encounter, like blood pressure.

And it runs headlong into the deeply ingrained belief that patients can control their weight if they put their minds to it.

Critics note that obesity is the top health concern in the United States, stoking Type 2 diabetes and hypertension, and contributing to heart disease, stroke and some cancers.

They say physicians should address weight as the No. 1 priority.

Ignoring a patient’s weight is missing an opportunity, said Dr. Caroline M. Apovian, co-director of the Center for Weight Management and Wellness at Brigham and Women’s Hospital in Boston.

“I can see doing this maybe 10 or 20 years ago, but now? Now that we have these great new treatments, why would you do this?” Apovian said, referring to powerful new weight-loss drugs and bariatric surgery.

If anything, she said, doctors should focus on the patient’s obesity before the medical conditions that often come with it.

“If primary care providers all over the country can address the obesity first and treat it, then in the long run we are going to reduce the incidence of all these other problems,” she said.

Body weight “is as much a vital sign as blood pressure and respiratory rate,” said Dr. Steven B. Heymsfield, a professor of metabolism and body composition at Louisiana State University’s Pennington Biomedical Research Center.

“Unless the patient is phobic around their weight for some reason, it makes no sense not to quantify it from the medical perspective,” he said.

While asking for a patient’s consent before weighing can foster “a more patient-centered approach,” said Dr. Fatima Cody Stanford, an obesity specialist at Harvard Medical School, “it is crucial that patients are informed about the options available to them, including weight management strategies, and that these discussions are approached with empathy and support.”