A Mysterious Health Wave Is Breaking Out Across the U.S.

Americans are unusually likely to die young compared with citizens of other developed countries. The U.S. has more fatalities from gun violence, drug overdoses, and auto accidents than just about any other similarly rich nation, and its obesity rate is about 50 percent higher than the European average. Put this all together and the U.S. is rightly considered a “rich death trap” for its young and middle-aged citizens, whose premature death is the leading reason for America’s unusually short lifespans.

But without much media fanfare, the U.S. has recently experienced a boomlet in good health news. In May 2024, the U.S. government reported that drug-overdose deaths fell 3 percent from 2022 to 2023, a rare bright spot in a century of escalating drug deaths. In June, the National Highway Traffic Safety Administration reported that traffic fatalities continued to decline after a huge rise in 2020 and 2021—and that this happened despite a rise in total vehicle miles traveled. In September, the U.S. government announced that the adult-obesity rate had declined in its most recent count, which ended in August 2023. Also in September, FBI analysis confirmed a double-digit decline in the national murder rate.

[Read: America fails the civilization test]

How rare is this inside straight of good news? Some government estimates—such as rates of obesity and overdose deaths—have reporting lags of one to two years, meaning that these causes of mortality are not necessarily all currently declining. Still, by my count, this year marks the first time in the 21st century that obesity, overdose deaths, traffic fatalities, and murders all declined in the official data analysis. The level of premature death in the U.S. is still unacceptably high. But progress isn’t just about where you are; it’s also about what direction you’re going in. And by the latter definition, 2024 was arguably the best year for American health reports in decades.

It would be convenient—for both efficient punditry and public-policy clarity—if a small number of factors explained all of these trends. After all, if we could isolate a handful of lessons, we could carry them forward and unleash a golden age of American health. Unfortunately, reality is messy and does not always comport with our preference for simple explanations.

Take, for example, the decrease in overdose deaths, which might be the most surprising news of the bunch. “This is the largest decline we’ve seen in recent data, going back at least back to 1999, which is remarkable because overdoses have been going up so steadily,” Charles Fain Lehman, a fellow at the Manhattan Institute, told me. But the exact cause of the decline is mysterious. “I could tell you a policy story,” he said, “such as the fact that we’ve made it easier for people to access drug-addiction treatment and we’ve significantly expanded the availability of Narcan”—an opioid antagonist that rapidly reverses the effects of overdose.

[Read: An anti-overdose drug is getting stronger. Maybe that’s a bad thing?]

But Lehman said he’s not convinced that these policy changes explain all—or even most—of the decline in overdose deaths. “Most of the evidence suggests that the effect size of these interventions should be small and universal across states,” he said. “But instead the U.S. is seeing a decline in overdose deaths that is both large and geographically concentrated in the East, where the overdose crisis started.”

According to Lehman, these facts point to other explanations. Maybe the overdose surge is burning out on its own. Drug waves tend to crest and fall in the absence of a coordinated policy response, because the people most likely to get hooked on any one generation of deadly drugs can’t remain indefinitely addicted—they either recover, seek treatment, or die. Or maybe a surge in suicides in 2021 created an unusual and unsustained spike in mortality. “This is grim, but for lack of a better phrase, folks who died during the pandemic can’t die later, and so maybe we should have always expected overdose deaths to decline” after the COVID crisis, he said.

Another possibility is that the fentanyl available on the street became weaker because of relatively lax immigration enforcement under the Biden administration. “There’s an idea known as the ‘iron law of prohibition,’ which says that the more intensive the law enforcement, the more intense the drug,” Lehman said. Perhaps as the risk of contraband confiscation at the border declined, cartels adjusted by moving more units of narcotics across the border while switching to a less concentrated product on a per-unit basis.

The frequency of maybes and perhapses in the above paragraphs makes my point. The decline in overdose deaths was either the direct result of good policy, the ironic result of bad policy, the mathematically inevitable result of lots of addicts dying during the peak pandemic years, or some combination of all three. Celebrating a nice-looking chart is much easier than understanding exactly what is making the line change direction.

A similar theme of uncertainty holds for the obesity story. This fall, the National Health and Nutrition Examination reported that the prevalence of obesity among U.S. adults declined from 41.9 percent to 40.3 percent in its latest sample of several thousand individuals. “Obesity prevalence is potentially plateauing in the United States,” one CDC official told The Washington Post. “We may have passed peak obesity,” the Financial Times’ John Burn-Murdoch wrote of the news.

[Read: The ‘peak obesity’ illusion]

Obesity has declined before by the government’s count, only to continue rising within a few years. One reason to think that this time is different is the rise of GLP-1 drugs, such as Ozempic and Mounjaro, which are remarkably adept at reducing appetite, leading to weight loss. Roughly one in eight Americans has taken a GLP-1 drug, and one in 16 is currently doing so, according to a survey by the health nonprofit KFF. It seems inevitable that as more Americans take therapies that put a lid on their appetite, obesity should mechanically decline.

Another possibility is that the developed world might be running up against a natural limit in overall obesity. In 2023, a team of Greek researchers wrote that obesity rates might stabilize in developed countries in the next few years, as “obesity has reached a biological limit … [or] a saturation threshold for the proportion of people who can become obese.” In fact, international evidence suggests that obesity has already “stabilized in children and adolescents of most economically advanced countries since 2000,” they wrote. (They also conceded that “the trends in adults are mixed and ambiguous and do not unequivocally support the obesity plateau hypothesis.”)

Finally, there’s the sudden decline in violent crime in the past few years—by some accounts, one of the fastest declines in homicide rates since the 1960s. One explanation is that the early 2020s marked the second time in a decade when the U.S. experienced the double whiplash of what some sociologists call the “Ferguson effect.” This theory holds that public outrage about police shootings reduces police activity and leads to an increase in violent crime. Adherents of this theory argue that in 2014, the death of Michael Brown created a backlash against policing, and in 2020, the death of George Floyd created another; in both cases, a high-profile killing created social unrest, which, they argue, may also have reduced police activity, possibly causing an overall increase in violent crime. As the health emergency wound down, policing picked up, and the spell of violence broke.

Another related explanation is that violent crime surged when lockdowns and other social disruptions unmoored young men from their routines in 2020 and 2021. But in the “great normalization” of 2022, young people returned to their pre-COVID schedules, and violent behavior quickly reverted to its pre-COVID rates. As John Roman, the director of the Center on Public Safety and Justice at NORC at the University of Chicago, told The Atlantic’s Rogé Karma, the beginning of the decline in violent crime coincided with the beginning of the 2022–23 school year, when pre-pandemic norms resumed for America’s teenagers.

This theory—that the pandemic created a brief bubble of abnormal and deadly behavior—would also explain why the U.S. saw an increase in auto fatalities during the first years of the pandemic. In March 2022, The Atlantic’s Olga Khazan summarized the berserk sociology of the moment pithily: “Everyone is acting so weird!” But, with time, people acted a little less weird. They resumed, among other things, their pre-pandemic manners of driving—that is to say, normally reckless, rather than completely out-of-control reckless.

[Read: The murder rate is suddenly falling]

Public policy may have played a small but meaningful role in declining crime and auto fatalities too. One creative explanation, from Bloomberg’s Justin Fox, is that Joe Biden’s American Rescue Plan sent hundreds of billions of dollars to governors and mayors, which allowed them to increase law-enforcement spending to crack down on both violent criminals and out-of-control drivers. In fact, state and local government spending increased in 2022 by nearly 8 percent, its largest annual increase since the Great Recession. This coincided with a voter push toward tougher policing standards, as “Minneapolis voters rejected a plan to replace the city’s police department,” “San Franciscans threw out their progressive district attorney,” and “New Yorkers elected a former cop as mayor,” Fox wrote.

At the heights of government power, there is currently a “rift” in the debate over “how to make America healthier,” as Gina Kolata of The New York Times recently pointed out. On one side are techno-optimists such as Elon Musk, who trust in science and technology. “Nothing would do more to improve the health, lifespan and quality of life for Americans than making GLP inhibitors super low cost to the public,” he posted on X. On the other side, Robert F. Kennedy Jr. is deeply skeptical of technology—as varied as nuclear power plants and the polio vaccine—and he has stressed that “lifestyle” is the more important determinant of health.

Kennedy gets this much right: Our lifespans are shaped as much by our behavior as they are medically determined by the health-care system. But rather than scaremongering about effective vaccines, we should be laser-focused on the truly scary causes of premature death in America and what it really takes to eliminate them—and on figuring out what’s gone right in the past few years.