Just like obesity, suicide, Zika, loneliness, road rage, opioid addiction, manspreading, peanut allergies, fake news and autism, insomnia is routinely described as an epidemic. Technically, an epidemic "is the rapid spread of infectious disease to a large number of people in a given population within a short period of time, usually two weeks or less." But, per the CDC, "non-infectious diseases such as diabetes and obesity exist in epidemic proportion in the U.S."

We're not too faithful to that definition in casual conversation. At some point, an epidemic became anything from a fatal, quickly spreading disease to whatever undesirable phenomenon ruffles someone's feathers. Is manspreading an epidemic? No, it's rude behavior that's probably been around as long as public transit has, but which recently got a catchy name and, as a result, more acknowledgement. Is autism an epidemic? No. Contrary to the claims of conspiracy-spewing ninnies like our president (and some perfectly nice, misinformed people, I'm sure), there is no evidence of a "tremendous amount of increase" in autism. Diagnostic-guideline changes in the '90s, coupled with increased awareness of the condition, sparked an uptick in the rate of autism diagnoses. But the actual prevalence has either stayed the same increased slightly. 

What about insomnia —Is clinical-grade sleeplessness a 21st-century scourge comparable to, say, obesity? Well, in 2014, the CDC declared insufficient sleep an epidemic, but that's not the same thing as an insomnia epidemic. Insomnia is a sleep disorder marked by frequent difficulty staying or falling asleep, or getting unrefreshing sleep, for at least a month — despite having the opportunity to get enough good sleep. If you're under-slept because of a screaming baby, an addictive Reddit-hole or a night-shift job, then you might be in the same sleep-deprived state as an insomniac, but for different reasons. 

It would be hard to say, with certainty, whether or not the prevalence of insomnia is much higher today than it was in past decades. But the data doesn't suggest that's the case, according to Michael Grandner, the director of the Sleep and Health Research Program at the University of Arizona: "There is a general idea that we're all more over-scheduled and stressed than we used to be and we're sleeping a lot less and a lot more poorly, but there really isn't evidence for that." It's worth noting that much of Grandner's research focuses on sleep disparities as a public health problem, so he's surely not in the "quit whining about your sleep deficiency" camp.

We probably are sleeping a little bit less than our parents did, but not by much. "As far as sleep duration is concerned," said Grandner, "there may be a slight decrease in sleep time over the past generation, but honestly, it's probably in the range of 15 minutes or so."

Changes in population-wide sleep quality are harder to measure because of how much our assessments of sleep have changed, said Grandner. "But," he added, "it doesn't seem to be that different when you compare reports from as far back as the 1970s, which is about as far back as good studies on the topic were done, at least as far as I could tell. So we are probably not sleeping much worse."

But something has changed drastically since the early '90s: how we react to bouts of bad rest. In a 2011 paper, published in the American Journal of Public Health, researchers from The University of North Carolina at Chapel Hill analyzed the medicalization of sleeplessness from 1993 to 2007, meaning the "process by which formerly normal biological processes or behaviors come to be described, accepted or treated as medical problems." 

To do this, researchers used data from a national survey of medical office visits and compared three different measures each year: the number of visits scheduled due to complaints of sleeplessness, the number of visits at which patients received insomnia diagnoses, and the number of visits at which patients got prescriptions for sleep meds. The goal of the study was to see if the number of complaints, diagnoses and Rxs grew proportionally over the 14-year period. In looking at the use of Rxs for rest, researchers included two classes of drugs: fast-acting anti-anxiety benzos like Xanax and Valium and z-drugs like Ambien and Sonata. Ambien, the first z-drug to hit the US market, wasn't available until 1994. So the study covered one year in a pre-Ambien America and 13 years with z-drugs on pharmacy shelves. 

Researchers found that visits for sleep complaints more than doubled between 1993 and 2007, from 2.7 million to 5.7 million. Insomnia diagnoses, by comparison, saw a seven-fold uptick — 840,000 to 6.1 million. But the rise of sleep-aid prescriptions blew them both out of the water, less due to benzos than to the heavily marketed z-drugs, which became the go-to choice for medicating sleep: The number of appointments yielding z-drug prescriptions jumped from 540,000 in 1994 to 16.2 million in 2007, an average of more than one million new prescriptions a year. This staggering growth, said Grandner, has likely leveled off in the years since, although it's hard to measure. 

And while 65-and-over patients are far more vulnerable to aging-related sleep changes, they weren't the ones gobbling up sleep drugs. The young-to-middle-aged adults were. Their complaints, researchers surmised, were probably due to "non-biological issues, including stress, multiple social roles, increased use of technology, or targeted marketing of sleep-inducing drugs." 

So, at a glance: In 1993, sleep complaints far outnumbered both insomnia diagnoses and sleep-med prescriptions. But, by 2007, sleep complaints and insomnia diagnoses were relatively equal. And both were far less common than prescriptions for sleep meds — millions of people who weren't insomniacs started taking drugs for insomnia. If insomnia diagnoses alone had increased, or if diagnoses and prescriptions had increased proportionally, then, researchers wrote, the data might suggest a true increase in the prevalence of insomnia as a stand-alone disease. But, that wasn't what happened.

A number of overlapping factors explain the data. For instance, awareness of sleep health (which is a good thing) probably factored in to some extent: Doctors increasingly diagnosed insomnia in patients who made appointments about health issues unrelated to their sleep issues. This suggests that sleep became something doctors asked about in relation to other maladies. Also, doctors started to view sleeplessness as a disease in its own right rather than as a symptom of another problem: Until 2006, sleep-challenged patients were most likely to be diagnosed with a mental illness. Then, the scales tipped, and poor sleep became the affliction of insomniacs. Same issue, new name. 

The introduction of z-drugs contributed to the medicalization of sleeplessness. There's nothing wrong with using effective treatments to, well, treat diseases. But, as sleep experts almost uniformly argue, z-drugs are not as effective on a long-term basis as behavioral (non-drug) insomnia therapy. And, Americans' love affair with sleep drugs doesn't necessarily translate to any deeper investment in sleep health. Grandner said he hasn't seen data to support the idea that we've grown more likely to pathologize sleep problems, meaning view them as abnormal enough to qualify as a disease.

"Anecdotally," he said, "I think people see sleep disturbances as a nuisance that they would like to medicate away, like a headache. Not a result of a set of lifestyle choices. So maybe we are more willing to recognize it. I don't know for sure whether we are more likely to take it seriously, though."

This story was originally published in February 2017