A new generation of breakthrough drugs promises to revolutionize the treatment of obesity. But there are concerns. Here's everything you need to know:
What's the excitement about?
For decades, researchers have chased a drug that could significantly reduce weight without dangerous side effects. Now they say that moment has arrived. A pair of drugs, Ozempic and Wegovy — different formulations of the compound semaglutide — have shown stunning effectiveness in helping people lose weight by suppressing their appetites. In a 15-month study by the manufacturer, the Danish company Novo Nordisk, obese people shed an average of 15 percent of their body weight, losing an average of 35 pounds each. They also lowered their blood pressure, cholesterol, and inflammation markers. A newer drug, tirzepatide, marketed by Eli Lilly under the name Mounjaro, has fared even better. In a study, users lost an average of 21 percent of their body weight. The revolutionary nature of noninvasive treatments that yield results comparable to gastric bypass surgery can't be overstated, say doctors. "It indeed is the transformative breakthrough," said Matthias Tschöp, a German physician and obesity researcher. The market for these drugs, doctors and weight-loss specialists agree, will be massive.
How many people might take them?
Tens of millions. Some 40 percent of Americans are obese, while another 30 percent have enough excess weight to elevate the risks for heart disease, cancer, and osteoarthritis. Morgan Stanley projects that "blockbuster" global sales of the new drugs will surpass $50 billion by 2030. Soaring demand for the drugs has already led to shortages, driven in part by an explosion of enthusiastic social media chatter. The hashtag #Ozempic has generated more than 700 million views on TikTok. So far, only Wegovy has gotten FDA approval for treating obesity; Ozempic and Mounjaro are currently approved only for treating diabetes, but are being widely prescribed "off-label" for weight loss.
How do the drugs work?
They are taken weekly in self-administered injections through a pre-filled "pen" like those used for insulin. In the body, the drugs mimic hormones naturally produced in the intestines that regulate blood sugar and hunger. Semaglutide mimics a hormone called GLP-1, while tirzepatide impersonates that and a second hormone, GIP. By sending signals of satiety to brain receptors that govern appetite, they give people a feeling of fullness after small meals and can make once-torturous cravings vanish. "It used to be that if I saw food, I would want to eat it," said Rachel Graham, a 54-year-old in Carlsbad, California, who lost 40 pounds on Mounjaro after years of failed diets. "Now, if I have three or four bites, I don't want to eat more."
Are there downsides?
Possible side effects include nausea, vomiting, diarrhea, and a racing heartbeat. Doctors say they're not common and improve with time and dose adjustments, but those who've had them say they can be debilitating. "I had no energy, constant nausea, and what I call power puking," said Anna Toonk, a podcaster in New York City who abandoned Ozempic. Since the drugs are new, it's unknown if there are long-term effects — and because patients who go off them typically gain their weight back, the drugs are likely a long-term and even lifelong proposition. That compounds another problem: the cost. Wegovy runs over $1,300 a month, Mounjaro close to $1,000. That puts them out of reach for many consumers, and insurance often won't cover them.
Previous generations of weight-loss drugs have a checkered history, and insurers have shared the long-standing view of obesity as a failure of willpower rather than a medical condition. That view is changing in the medical community, due to a mountain of evidence that body weight stubbornly resists change and that for most obese people, dieting and exercise produce only temporary weight loss. "We now understand obesity isn't a character flaw," says W. Scott Butsch, an obesity medicine specialist at the Cleveland Clinic. "It's a dysfunction of the complex system that controls body weight." He and other experts hope the new drugs will lead to insurance changes. But given the number of potential users, the price tag for drugs like Mounjaro could be staggering for private insurers, Medicare, and Medicaid. Obesity experts say there are other reasons the miracle drugs give them pause.
What are the concerns?
Doctors worry that if a weekly shot can produce weight loss, people will dismiss the need to exercise and improve their diets. Advocates for fat acceptance fear the drugs will increase stigma around weight and pressure on overweight people to conform to a punishing social standard of thinness. Another concern is that the drugs are already being used by people who are not obese but have seized on them as an easy way to shed 5 or 10 unwanted pounds. Such worries, though, are outstripped by excitement about the drugs' transformative potential. Medicines that can help patients shed 30 to 50 pounds or more are a "game changer," said John Buse, an endocrinologist at the University of North Carolina medical school. "Obesity is on the ropes."
Taking Hollywood by storm
The steep price of the new weight-loss drugs is a barrier for many — but it hasn't slowed an explosion of interest among celebrities and wealthy urbanites seeking a shortcut to thinness. Ozempic is "the drug of choice these days for the 1 percent," said Paul Jarrod Frank, a dermatologist on Manhattan's Upper East Side. "Everybody is either on it or asking how to get on it." In body image-obsessed Hollywood, Ozempic has "saturated the industry," reports Variety, with interest snowballing after reports that Kim Kardashian used it to drop 16 pounds and fit into Marilyn Monroe's dress for last year's Met Gala. She denies it, but Elon Musk says semaglutide helped him lose 30 pounds. It's "the Hollywood drug," said Patti Stanger, executive producer of the reality show The Millionaire Matchmaker. "Everybody I know is on it." The use of Ozempic by the non-obese, however, has yielded a new side effect: Dermatologists and plastic surgeons report a spike in visits from people complaining that sudden weight loss left their cheeks hollow and sagging. "I see it every day," said Frank, who coined a term for the condition: "Ozempic face."
This article was first published in the latest issue of The Week magazine. If you want to read more like it, you can try six risk-free issues of the magazine here.