A shortage of shut eye can leave you feeling tired, cranky, hungry and irritable. But it turns out, a lack of sleep can affect you in a lot of ways that go beyond triggering those basic feelings. And that’s a problem, since 53 percent of Americans are snoozing less than the recommended seven hours each night, according to the National Sleep Foundation. So what can a shortage of shut-eye cause? Only some of the crazy effects that follow.
YOU DREAM UP THINGS THAT NEVER HAPPENED
How about this for a mind game: Sleep deprivation can actually increase your chances of developing false memories, research from the University of California at Irvine found.
After a night of no sleep, people were more likely to report they saw incorrect information in a series of photos they viewed in the morning—when in reality, they just read those fake details in a separate narrative afterward and unconsciously merged them into their memory. But people who saw the photos at night and then got an adequate night's sleep didn’t “misremember” anything when tested in the morning.
According to study author Steven Frenda, Ph.D., the part of our memory that “encodes” the initial experience may be especially influenced by lack of sleep. “So things we see and experience when we are sleep deprived could be more vulnerable to distortion at a later time,” he says.
YOU STIR UP TROUBLE AT WORK
You want to strangle Bob from accounts payable for his open-mouthed chewing even when you’re rested and chipper. So it’s no surprise that when you’re skimping on sleep, you become a little more testy on the job. And those feelings can translate to some acts of office disobedience, according to researchers at the University of North Carolina at Chapel Hill.
The researchers found that when nurses slept less than six hours the night before, they were more likely to engage in acts of workplace deviance than their well-rested peers. That means things like spilling confidential information, spending time on personal work, saying something hurtful to a coworker, or working slow on purpose.
Why the deviant direction? The scientists aren’t sure, but they believe the lack of sleep depletes your ability to self-regulate your emotions and your behavior, making you more likely to do something you’d consider destructive in other cases.
YOUR SWIMMERS SUFFER
Even if you’re not too tired to get it going in the bedroom, poor sleep may affect your sex life in another way: Lack of sleep can sink your swimmers, found a study from Denmark.
Men who measured highest on qualities of disturbed sleep—restless sleep, inability to fall asleep, or waking up often and staying awake during the night—had a sperm count that was 25 percent lower than those who snoozed more peacefully. They also had fewer sperm with normal size, shape, and movement.
The researchers think that disturbed sleep can mess with your testosterone rhythm at night, which can affect semen quality. Future research will test if getting your zzz’s back on track will help your swimmers, too.
YOU WEAR PERMANENT BEER GOGGLES
You don’t need a few pints to end up with a serious case of beer goggles—a lack of sleep might give you the same thing, research from Hendrix College suggests.
When men were sleep deprived, they rated photos of women considered least attractive and moderately attractive as significantly hotter than they did when they had enough sleep. What’s more, they also reported greater interest in having casual sex with them when they were short on sleep.
“We think that increased activity in the reward centers of the brain and decreased inhibitory activity in the frontal lobe might explain these findings,” says study author Jennifer Peszka, Ph.D. And when your cognitive resources are depleted by sleep deprivation, you can’t put them toward discerning a potential partner. The result: You become less picky.
Hanging around yawning ladies won’t increase your chances of getting lucky, though. Sleep-deprived women didn’t raise their ratings of unattractive guys or their interest in having sex with them, the study found.
YOU BECOME A LIGHTWEIGHT
You’d never drive after you had one too many, right? But if you’re short on sleep, that one drink can actually feel like quite a bit more.
Researchers from Australia found that when people with a blood alcohol concentration of 0.03—about two beers over 90 minutes for a 175-pound guy—were kept awake for up to 21 hours, they drove worse on a simulated road test than those who drank more—a BAC of 0.05—but were well rested. The sleepy drivers also showed slower reaction times, more lane crossing, and greater changes in speed.
Both alcohol and sleepiness are associated with higher crash rates, the researchers say, but the combination of the two of them together exacerbates the effect. So if you’re spending all night at the bar after waking at dawn that morning, play it safe and take a cab home.