Robert F. Kennedy Jr. has some thoughts about Ozempic. The government should not provide the drug to millions of Americans but instead fight obesity and diabetes by handing out organic food and gym memberships, according to the nominee to lead the Department of Health and Human Services. Like many of RFK’s statements, these ideas have sparked some outrage. But its basic premise — that Americans should control their weight through better diet and exercise — couldn’t be more common.

But this common-sense philosophy of weight loss, as espoused by RFK, the FDA and, in fact, just about every doctor you’ve asked lately, has lately been out of sync with the science.

Lifestyle interventions have been central to the country’s decades-long attempt to curb chronic disease rates. Eat less, move more: This advice applies to almost everyone, but for those who are obese or overweight – about three-quarters of the U.S. adult population – diet and exercise are considered the most important ways to improve their health Health. Even now that doctors have access to Ozempic and related GLP-1 drugs that produce lasting weight loss and a variety of life-extending benefits without the need for surgery, behavioral change still takes precedence. Formal treatment guidelines for obesity have more or less endorsed RFK’s approach, arguing that “lifestyle therapy remains the cornerstone of treatment.” And according to the government, the drugs themselves are only suitable “as a supplement” to a reduced-calorie diet and increased physical activity.

This insistence on the status quo now seems a bit strange. It has long been known that prescribing diet and exercise to treat obesity simply isn’t that effective. People could, at least initially, lose enough weight to prevent or control type 2 diabetes, said Tom Wadden, an obesity researcher at the University of Pennsylvania who has been involved in clinical trials of both lifestyle changes and GLP-1 drugs as treatments Obesity. But he told me that weight loss can’t reverse sleep apnea or prevent heart attacks or strokes.

For people with severe obesity today, even the modest benefits of diet and exercise seem irrelevant. In recent years, clinical trials of Ozempic and related drugs have shown that the “cornerstone” of treatment contributes almost nothing to the effects of these drugs on people’s body weight.

The very possibility that diet and exercise are no longer as important as they once were has caused some unease in the field. “I’ll answer cautiously,” said David Saxon, an obesity specialist at the University of Colorado Anschutz Medical Campus, when I asked him about it last spring. “I don’t want you to quote me and say, ‘He doesn’t think lifestyle is important.'” With older obesity medications, he said, there is evidence to recommend diet and exercise first (and beyond). prescribe Clearly: In clinical trials, patients who received a lifestyle intervention in addition to medication lost twice as much weight as those who did not receive it.

From the June 2024 issue: Ozempic or Bust

But the data tells a different story for the newer drugs, Saxon and other doctors told me. In most clinical trials of GLP-1, patients receive the drug in combination with a modest lifestyle intervention: monthly, 15-minute check-ins with a counselor, for example, and advice to reduce calorie intake and exercise for a few hours each week Is it worth doing sport, e.g. B. to go for a walk. In one of Wegovy’s large studies called STEP 1, this approach resulted in participants losing weight of about 15 percent of their body weight. Another study of Wegovy called STEP 3 tried even more: Participants were offered biweekly appointments with a registered dietitian and spent the first two months on the drug eating very low-calorie meal replacements . There’s evidence that without Wegovy, all this extra coaching would make a big difference to people’s health. But for the people who took Wegovy, the benefits were negligible: Participants in the STEP 3 study lost an average of 16 percent of their body weight, just a hair more than participants in the STEP 1 study. “This suggests that the intensive lifestyle program with these new medications may not be necessary,” Saxon said.

He’s seen this play out in the Veterans Affairs system, where he also works. Patients who received the older, less effective anti-obesity drugs were expected to participate in an ongoing lifestyle change program with monthly checkups, Saxon told me. Now that he and his colleagues are prescribing GLP-1, “we’re not really prescribing it anymore,” he said, “because we see that even without GLP-1, people are maintaining their weight loss with these newer drugs.” Eduardo Grunvald, the medical director of the weight management program at UC San Diego Health, told me he had the same impression. “The bottom line is that you don’t necessarily need an intensive lifestyle intervention for these medications,” he said when we spoke in March.

Still, obesity specialists, including Saxon, haven’t given up on diet and exercise. But the field has begun to reevaluate the nature of such guidance. “We need to figure out what it’s going to look like,” Sue Yanovski, co-director of the Office of Obesity Research at the National Institute of Diabetes and Digestive and Kidney Diseases, told me. Since last year, a number of reviews, editorials and perspective pieces, most published in obesity journals, have addressed this very question. For example, one article argued that obesity specialists should not aim to achieve “quantity” of weight loss but should emphasize its “quality.” A co-author of this article, obesity doctor and epidemiologist Kristina Lewis of Wake Forest University, told me that GLP-1 drugs do not make diet and exercise irrelevant; In fact, they give patients the opportunity to “focus on lifestyle interventions in a more refined way” by eliminating cravings and highlighting the need for calorie counting. She said people taking Ozempic and their doctors might consider switching to a healthy diet, being more active and getting more sleep. All of these procedures are beneficial regardless of your weight.

This all sounds very reasonable, but in a larger context it also feels like a concession. For decades, the harshest critics of the weight loss industry and its associated doctors have been saying something similar: Healthy behaviors can and should be disconnected from people’s single-minded goals smaller. Ironically, the principles of this movement that became known as “Health at Every Size” are now being applied to the treatment of obesity.

But if lifestyle interventions are supposed to have the same benefit for people diagnosed with obesity as they do for anyone else, then how special is their role in treatment? Lewis and other doctors told me that people taking Ozempic may still need individualized diet and exercise advice because rapid weight loss can lead to special health needs. For example, clinical studies found that people who took GLP-1 drugs lost a lot of muscle and bone mass as their bodies shrank; In fact, these and other lean tissues were responsible for 25 to 40 percent of their total weight loss. To reduce the additional risk of weakness or fractures that could result, some experts now suggest that people taking these medications should eat more protein and do more strength training than they would with a traditional lifestyle intervention .

Read: The science behind Ozempic was wrong

Advice on muscle-building diets and workouts could be part of standard care for people on Ozempic. “Rationally, I would say we should do this,” Wadden, who was a member of the research team for the STEP 1 and STEP 3 studies, told me. Still, he acknowledged that the evidence for this approach is not yet complete. Wadden has been studying lifestyle interventions for people with obesity for decades. Some of this research found that adding strength training and aerobic exercise to very strict diets did nothing to prevent the disappearance of lean body mass. The people who did these workouts were “really swimming against the tide” of the effects of rapid weight loss, he told me. Other obesity researchers have disputed the idea that muscle loss is even a problem. A current paper from the Journal of the American Medical Association argues that the link between physical frailty and GLP-1 drugs is not supported by the data, noting that if someone loses more than half the weight taking Ozempic to be fat, they will certainly end up with more Muscle to fat ratio than before.

Read: The Illusion of “Peak Obesity.”

Doctors still don’t fully understand why people who take GLP-1 lose so much weight to begin with. Ozempic may be working on its own to encourage different eating habits, Wadden told me. “The drug dramatically changes your diet without much conscious effort,” he said. “How is it changing? We don’t know.” People who take the drug may end up eating less overall despite sticking to their previous diet: say, one Pop-Tart for dinner instead of five. (In this case, meetings with a nutritionist would be very helpful.) But the drugs could also help change people’s tastes. “Suddenly you like more fruits and vegetables,” Wadden said, “and you like lean proteins.” Similar questions could arise about exercise: just the act of losing a lot of weight could lead someone to do more physical activity , regardless of whether he has access to a gym or spends time with a trainer. The studies that could clarify this have not yet been carried out.

Wadden, like many other doctors, remains convinced that diet and exercise should continue to be the standard treatment for people who are overweight or moderately obese. But for people who need to lose more weight — say, the tens of millions of Americans whose BMI is over 35 — he now believes the rules are changing. For this group, he said, “I no longer believe that lifestyle change is the cornerstone of obesity treatment.”

What have you experienced while taking GLP-1 medication? Share your story with us.

(By writing to us, you agree to this The Atlantic Use your answer, which we may edit for length or clarity. You agree to that too The Atlantic‘S Reporters may contact you at the address provided to discuss whether you would be willing to be interviewed.)