The Ozempic effect is finally showing up in obesity data

For years, obesity rates in the US have gone in one direction: up. From the first year it was launched, Gallup’s National Health and Well-Being Index has found that the share of US adults reporting obesity has climbed and climbed, rising from 25.5 percent in 2008 to 39.9 percent in 2022. That survey caught the last leg of an epidemic that has been spreading for decades, with estimated obesity prevalence tripling over the past 60 years.

It’s not that the country hasn’t tried to fight weight gain. But from the $33 billion Americans spend each year on weight loss products and services to government efforts like first lady Michelle Obama’s Let’s Move campaign or Make America Healthy Again, little has worked. Many doctors and patients came to believe the rise in obesity may be all but biologically inescapable, despite the grave health risks that accompany it.

But maybe not. According to the latest results from Gallup’s survey, self-reported obesity has started to fall, declining by nearly 3 points to 37 percent in 2025. The self-reporting part is an important limitation — people’s reporting of their weight tends to be imprecise — and we’ll need more definitive proof from the Centers for Disease Control and Prevention to be sure, but it’s some of the earliest evidence that the US may finally be turning a corner on one of the biggest health crises of the modern age.

And the main reason it appears to be happening isn’t because weight-loss experts have stumbled upon a new diet that always works (we haven’t and probably never will) or because we’ve managed to ban all unhealthy junk food (we haven’t and almost certainly never will). It’s likely because of the growing use of glucagon-like peptide-1 agonists, better known as GLP-1 drugs like Ozempic and Wegovy.

What’s changed is we now have highly effective weight-loss medicines working at a scale that we’ve never seen before.

Older weight-loss drugs tended to shave off only a few percentage points of body weight, and they came with tough trade-offs and quick weight rebound. The new drugs, which were originally developed to treat diabetes, are targeting the biology that makes weight so hard to lose and keep off: They dial down hunger in the brain, slow gastric emptying, and improve post-meal insulin signaling. In large randomized trials, semaglutide 2.4 mg — the active ingredient used in medicines like Ozempic — produced about 15 percent average weight loss over 68 weeks when paired with basic lifestyle support. Other combinations have reached as much as 20 percent on higher doses.

Those effect sizes are big enough that, when even a modest share of adults use them, you can start to see movement in the population data. And as further data from Gallup shows, more and more Americans are trying these drugs, with the survey finding that more than 12 percent of adults reported taking them in the second and third quarters of 2025, up from less than 6 percent in early 2024.

And while much of the media coverage around these drugs has focused on weight and appearance, the health benefits seem to go much further. In 2024 the Food and Drug Administration added cardiovascular risk as a reason to be prescribed the GLP-1 drug Wegovy, grounded in results from a major trial that showed fewer heart attacks, strokes, and cardiovascular deaths in adults with obesity or overweight and established heart disease. The FDA’s action also opened a door for Medicare coverage in patients with cardiovascular disease — an early sign that access for these expensive medicines could expand beyond the well-insured.

The upside of downsizing — and the side effects

It’s still early days, but if the national obesity curve keeps bending down, the benefits would be enormous. Obesity multiplies risk across nearly every major cause of death; even small, sustained declines in prevalence translate into millions fewer people living with diabetes, heart disease, sleep apnea, and painful joint disease — and billions saved in medical costs over time. The CDC pegs direct medical spending tied to obesity at roughly $173 billion. Turning that curve even a little would represent significant relief.

But we’re a long way from solving this problem. For one thing, as effective as they are, these drugs behave more like statins than antibiotics: They work while you take them. When people stop, weight regain is common.

And GLP-1s do come with side effects that for some patients have been serious enough to lead to discontinuation. Scientists also still aren’t sure about some of the longer-term effects of the drugs, which can include muscle loss and changes to sex drives. And don’t forget the four-figure monthly side effect on the wallet if GLP-1s need to be paid for out of pocket. Obesity is already linked to lower socioeconomic status, and that disparity could worsen if GLP-1s remain out of reach for all but high-income people.

Chances are, though, that the current generation of GLP-1s is the worst and most expensive we’ll ever have. Drug companies are already experimenting with pill forms of the medicine, which would make dosing more precise and lower the barrier to access: as much as 20 percent of the American public has some form of needle phobia (or trypanophobia, for those who want a great Scrabble word).

I’ll admit there’s something uncomfortable about the idea of solving obesity primarily through a drug. After all, as Health Secretary Robert F. Kennedy Jr. is fond of saying, can’t we fix obesity through healthier food and more exercise? But while our food system could surely be improved and most of us don’t get enough exercise, it’s not as if we haven’t tried, whether as individuals or as a country. The simple fact is that the contemporary environment is one that is heavily weighted toward the obesogenic. GLP-1 drugs seem to offer the best chance to tilt the scales back in our favor.

A version of this story originally appeared in the Good News newsletter. Sign up here!