Nearly a decade has passed since the American Medical Association first classified obesity as a chronic disease, one that can require medical interventions beyond diet and exercise.
Now, as the blockbuster medications Wegovy and Ozempic rise in popularity, they are bringing more attention and adding complexity to cultural and medical conversations about weight and weight loss.
Both drugs are brand names for semaglutide, a medication that can lower blood sugar levels and suppress the appetite. Ozempic is approved to treat Type 2 diabetes in adults, while Wegovy is approved for weight loss in two groups: Those 12 and older with obesity, and adults who are overweight and also have least one weight-related health condition, such as high blood pressure or cholesterol.
Patients and doctors say the results they're seeing from the drugs further underscore the consensus that lifestyle changes alone are often insufficient for people trying to lose excess weight.
"Two-thirds of Americans did not wake up one morning and choose to be overweight or to have obesity. This is not a behavioral choice or behavioral disease. This is a chronic disease — a chronic, treatable disease — and we should treat it like we treat any other disease, with medications and with interventions that target disease mechanisms," said Dr. Ania Jastreboff, an associate professor at the Yale School of Medicine. She serves on the scientific advisory board of Novo Nordisk, which makes both medications.
Stacey Bollinger, an account director in Maryland, said that when she started taking Wegovy last January, she'd exhausted most other options to improve her physical health. She was prediabetic, her joints hurt and her asthma was flaring up. But she had been working with a nutritionist, following a healthy diet and doing regular strength training and cardio exercises for about a year.
"I went for my physical and it’s one of those things where it’s like, I know the doctor is going to tell me that I’m overweight. It is not shocking," she said. "I see it. I feel it physically. But also, I just feel miserable. Let’s have a conversation about what options I do have."
On Wegovy, Bollinger said, she has lost more than 50 pounds, down from 266. She said she feels more energetic, her asthma is better controlled and her feet, ankles and knees don’t ache at the end of the day. At a recent checkup, her bloodwork showed that she was no longer prediabetic.
"I really don’t think I would have had this loss without Wegovy," she said.
Novo Nordisk describes Wegovy as a long-term treatment, noting that just as a patient with high blood pressure sees a rise after stopping medication, people on Wegovy can regain weight if they go off the drug.
"Obesity is a chronic, progressive and misunderstood disease that requires long-term medical management," it said in a statement.
"One key misunderstanding is that this is a disease of willpower, when in fact there is underlying biology that prevents people from losing weight and keeping it off," the company added. "Just like any other chronic disease, such as high blood pressure or high cholesterol, obesity should be treated as such."
Why obesity has become more common
Semaglutide is part of a class of drugs called GLP-1 agonists, which mimic a hormone that signals to the brain when a person is full.
"This particular medication stimulates the pathway of your brain that tells you to eat less and store less, and then it down-regulates the pathway of your brain that tells you to eat more and store more," said Dr. Fatima Cody Stanford, an associate professor of medicine at Massachusetts General Hospital.
Read more about Ozempic and Wegovy
- What it’s like to take Ozempic and Wegovy, from severe side effects to losing 50 pounds
- As weight loss drugs soar in popularity, many who could benefit can't get them
- Wegovy supply expected to improve in the next few months, company says
- What happens when you stop taking a weight loss drug? Many people gain the weight back
She said that more important than inducing weight loss, the medications can lower the risk of health issues associated with obesity, including diabetes, heart disease, stroke and some types of cancer.
"A lot of people presume that we’re targeting a size" when prescribing the drugs, Stanford added. "I’m never targeting a size with a patient. I’m targeting their health."
Obesity rates have been rising in the United States since the 1980s. In the four years leading up to 1980, the obesity rate was 15% for adults and 5% for children and adolescents. Those numbers climbed to 42% and 20%, respectively, during the period between 2017 and early 2020, according to the Centers for Disease Control and Prevention.
The reasons for that increase are complex, but medical experts generally attribute it to interactions between genetics and societal and environmental changes.
One leading explanation for obesity is that bodies try to maintain a particular baseline, or set point, of fat. On a population level, changes in the environment and behaviors have increased fat set points over time, Jastreboff said.
On average, people now engage in less physical activity, eat more processed food or larger servings, get less sleep and experience more stress than past generations, which may prompt bodies to maintain a higher baseline of fat.
That might explain why some people struggle to lose weight through lifestyle changes, or why others regain weight lost on a diet.
Individual genes can determine how the body responds to external factors, so they may trigger obesity in some but not others. A theory known as the "thrifty genotype hypothesis," for example, suggests that some people store more energy as fat thanks to genes inherited from ancestors who needed that storage to survive famines.
Ozempic and Wegovy can help lower a person’s fat set point, Jastreboff said. Semaglutide was shown in trials to cut body weight by around 15%. By contrast, a 2018 study found that at best, diet, exercise and behavioral counseling help people lose an average of 5% to 10% of their body weight.
"Some people can lose weight with just behavioral changes, but some people cannot. Why do we have a problem with that?" said James Zervios, vice president of the nonprofit advocacy organization Obesity Action Coalition. "Why is it that we continue to lean one way and say, 'Well, we’re just going to tell someone to journal their food. We’re just going to tell someone to go for a walk at night after dinner.' If that works, you wouldn’t be dealing with the number of people that are experiencing obesity or severe obesity right now."
Debates about obesity medications continue
The notion that obesity should be addressed through just diet and exercise is still pervasive, however.
"Unfortunately, the public viewpoint is that, if a person takes a medication, they’ve taken the easy way out to lose weight," said Rebecca Puhl, deputy director of the University of Connecticut’s Rudd Center for Food Policy and Health.
Even some doctors don’t yet feel comfortable prescribing the new obesity medications. Stigma can play into those decisions: Research has shown that physicians harbor similar levels of weight bias as the general population, and medical school training rarely addresses stigmas around weight, Puhl said.
On the other side of the coin, some people active in the fat acceptance movement say that many of those considered "overweight" by medical definitions are healthy and don't need interventions.
A 2017 study of 3.5 million health records in the United Kingdom found that although obesity increased people's risk of diabetes, high blood pressure or high cholesterol, around 15% of those with obesity did not have those conditions.
In a BuzzFeed editorial last month, Evette Dionne, a culture journalist and MSNBC columnist, suggested that the medical establishment is now more focused on weight loss drugs than on fixing systemic issues linked to obesity risk, like food deserts.
"It is objectively a good move to unlink the idea of moral virtue from fatness. However, in these attempts to complicate our cultural understanding of fatness, the remedy remains the same: lose weight rather than changing the ways in which our society interacts with and treats fat people," she wrote.
Puhl said that while debates about obesity treatment are important, decisions about using the medications should be between a patient and a doctor.
"We don't want medication to be used as a default strategy and we want for sure the risks and side effects to be considered," she said. "But we also need to respect that, for some people, medication can be very helpful."