You may boast that you’re already asleep before your head even hits the pillow, but if you’re conking out that quickly, here’s your wake-up call: That’s a clear sign of sleep deprivation. And that’s just one of the warning signs that you need to get more shut-eye.
1. You fall asleep immediately. You might chalk this up to being a good sleeper, but the opposite is true. If you routinely fall asleep within five minutes of lying down, you probably have severe sleep deprivation, possibly even a sleep disorder, according to the National Institute of Neurological Disorders and Stroke.
2. You’re more impulsive than usual. Grabbed a donut at the morning meeting when you normally wouldn’t touch it? Splurged on that expensive top you’ve been eyeing online? A lack of sleep may be to blame. “The prefrontal cortex is greatly affected by sleep deprivation,” explains Harris. “This area is associated with judgment, impulse control, visual association and attention. Less sleep leads to poorer judgment and acting impulsively, e.g. poor eating when sleep deprived, buying things without thinking about the consequences, irritability and mood issues with others.”
3. You’re relying on clichés. If you find yourself throwing around phrases like, “Beggars can’t be choosers” and “Better safe than sorry,” and you’re not currently in retirement, it may be time to take a nap. “The frontal lobe is associated with speech, constructive thinking and novel thinking/creativity and is greatly impacted by sleep deprivation,” notes Harris. “Sleep deprived people find it difficult to have spontaneous complicated speech, leading to more slurring, use of clichéd phrases, stuttering and monotone speech.”
4. You’re forgetful. If you ran out of the house to mail your dad’s birthday card only to realize you—once again—left it on the kitchen counter, or you completely blanked on a new coworker’s name despite hearing it several times, a lack of rest may be messing with your memory. Sleep leads to memory consolidation and emotional processing, according to Harris. “Without proper rest, it’s harder to form memories,” she notes. “It is harder to put emotional memories into context, and thus, it is more difficult to act rationally and thoughtfully.”
5. You’re hungrier than usual. When you don’t log enough sleep each night, it’s harder to stop yourself from downing a bag of chips, followed by a scoop or two of ice cream. Here’s why: Sleep deprivation can increase your appetite by affecting two key hormones in our body: leptin and ghrelin. “Leptin is the hormone that tells our body to stop eating, giving us the sensation that we are full,” explains Harris. “Ghrelin, on the other hand, is a hormone that gives us a hunger signal and tells us to eat. When we don’t get enough sleep, the leptin/ghrelin balance is shifted, with a drop in leptin and an increase in ghrelin.” In a nutshell, without a good night’s sleep, the hormone telling us to eat more increases, while the hormone that tells us to stop eating decreases.
6. You’ve read this sentence twice. An inability to concentrate is a sure sign that you’re not spending enough time with your eyes closed. Along with a lack of focus, not getting enough sleep also impairs your ability to make split-second decisions, according to a 2009 study in the journal Sleep—the kind of decision-making that can come in major handy, say, when driving and trying to avoid a near accident.
7. You’re clumsy. Some people seem to be naturally clumsy—like the adorable, ever-falling Jennifer Lawrence—but skimping on sleep can also cause issues with motor skills, such as being unsteady on your feet and stumbling when carrying your things, notes Harris.
8. You’re fighting with your partner. Your partner may have ticked you off or you may just be tired—or both. A 2013 U.C. Berkeley study found that couples have more frequent and serious fights when they don’t get enough sleep. The researchers note that the lack of shut-eye makes it harder to avoid and handle conflict.
9. You’re zoning out. If you’re spacing out while driving, such as missing your exit on the freeway or doing things throughout the day with little memory of them later on—in other words, coasting on automatic pilot and not really being aware and in the moment, according to Harris—you need to get more sleep. (But not all zoning out is bad.)
10. You conk out at the movies or during a daytime flight. Falling asleep the minute you enter a dark or dull environment, particularly if it’s during daylight hours, is one of the hallmarks of sleep deprivation. If you’re getting enough sleep, you should be fairly peppy and alert during the day. It is daytime, after all.