WASHINGTON—A hot new trend sweeping the country’s adult population has turned into a nationwide sensation, sources confirm, but many experts say the burgeoning grown-up fad may be a cause for significant concern.

It’s called “plateauing in your career and relationship,” and it involves adult men and women hitting a wall in their professional and romantic lives and doing absolutely nothing to reinvigorate them, an activity that researchers at University of Chicago’s Department of Comparative Human Development warn may be, while popular, highly dangerous and unhealthy.

Statistics show that a disturbingly high proportion of adult Americans—nearly three-quarters, according to the university’s findings—engage in the new craze, which includes spinning your wheels by losing track of what got you excited about your job and partner in the first place, experiencing no upward mobility in your professional life nor any emotional or sexual growth in your romantic one.

“We’re seeing a lot of adults all across the country getting together and doing 10, 15 years of comfortable routines at work and at home, losing touch with any real passion or energy that they presumably had for their partners or jobs, and gradually slipping into a kind of numbed routine devoid of variation or joy,” said lead researcher Susan McClintock, adding that wondering why one ever embarked on a particular career path or relationship to begin with is a particularly popular variant of the trend. “They’ll start out by not putting a lot of effort into a report that could have gotten them a promotion, or forgetting an anniversary. Pretty soon they’ve full-out ‘plateaued’ in their professional and personal lives, and the driven, passionate selves they once knew are just a distant blip in the rearview mirror.”

“They see their friends doing it, and then they join in,” McClintock said. “They don’t seem to be deterred by the consequences—which include everything from floating anxiety, quiet bitterness, and a relentless sense of dissatisfaction and disillusionment. In many cases, it’s that numb sense of indifference that they’re actually seeking out. That’s the payoff.”

Data from the investigation helped shed light on the possible motives for the massively popular but disturbing trend, which include the fact that it’s just easier this way and that moving forward at work and in relationships requires motivation, foresight, and planning, and that’s hard—especially as time goes on and the years start to add up and it’s just hard to find the energy anymore.

Further research suggests that these so-called plateauers enjoy life-plateauing in public, right out in the open, and often in tandem with a coworker, best friend, or spouse.

“Because this fad has become so widespread, and because a whole culture and way of life seems to have formed around it, it’s become very hard for non-adults to step in front of this trend and say, ‘This is dangerous, and we need to put a stop to this,’” McClintock said. “Our only hope is that adults will soon grow tired of plateauing and move on to whatever the next hot new thing is.”

Sources confirmed that plateauing in your career and relationship is merely the latest fad to grip adults in recent years, following on the heels of popular trends such as giving up on your dream of writing a novel, having kids because it’s a box to check, and gradually feeling alienated in your own body after steady weight gain.