If you haven’t gotten enough rest the night before, the telltale sign could sit right on top of your nose. Acne can flare up when you aren’t getting enough sleep. In fact, sleep deprivation is considered one of the three main acne triggers, along with stress and sweating. Studies have borne this out. It’s possible that by disrupting your hormones, sleeplessness also unsettles the chemical balance in your skin that wards off pimples.
Puffy Eyes and Dark Circles
Sleeplessness takes its toll on your face. Researchers have found that your mouth, forehead, and eyes can reveal to others that you aren’t getting enough rest. In particular, one of the hallmark signs of sleepiness is the presence of dark circles and puffy eyes.
Not all dark circles come from sleep loss, but it is often a contributing factor. One study looked at 200 subjects, mostly women, who had periorbital hyperpigmentation—the medical term for dark circles around their eyes. Of these subjects, 40% suffered from lack of adequate sleep, including insomnia.
In another research test, observers were asked to rate the faces of subjects. A photo of each subject was taken after a full night’s sleep, and another was taken after only 5 hours of sleep, followed by 31 hours of wakefulness. Observers identified the well-rested faces as being more alert, youthful, and attractive most of the time. They also noted eye puffiness and dark circles as one of the most obvious signs the subjects didn’t get enough sleep. Not only that, but the observers judged faces with little rest as appearing sadder as well. So if you want to give off a cheerful vibe, make sure you’re in bed at bedtime.
Sleep Loss Can Lead to Weight Gain
If you’ve had trouble sleeping recently, don’t be surprised if you gain a few extra pounds. Less than six hours of sleep per night puts you at an increased risk of obesity. To understand why, you need to know how sleeplessness affects your body.
When you lose sleep, your body chemistry changes. The hormones that control hunger become imbalanced, leading you to feel hungry more often. You also become less sensitive to insulin, the chemical that lets you absorb the energy from sugar.
The results of these changes have been shown in the laboratory. People forced to go without sleep eat more—particularly high-carb snacks. Those results were confirmed in at least two studies. So if you aren’t getting enough time in bed, watch out for the munchies. They seem to be harder to control when you go without sleep.
Craving Salt, Sugar, and Junk Food
Salty and sugary snacks are especially hard to avoid when you don’t get enough zzzs. Your body seems to crave higher-calorie foods when you’re tired. Given that many calorie-packed foods are sweet or salty, this connection makes sense.
Aside from the obesity risks discussed earlier, eating too much salt and added sugar has been associated with serious health problems. Getting too much sugar puts you at greater risk of diabetes and heart disease, among other conditions. Too much salt can damage your heart and kidneys, and may also harm your bones.
Sipping More Caffeine
When you don’t sleep enough, the magical power of caffeine to perk you up and keep you moving diminishes. Regular coffee drinkers may notice that after a few days of inadequate sleep, their morning joe does little to wake them up.
This has been shown through research. One study gave participants only five hours of sleep for five days in a row. Some of the participants got 200mg of caffeine (about as much as a cup of coffee), and some got a placebo in a double-blinded test.
It didn’t take long for the results to kick in. After three nights of poor sleep, participants who received caffeine no longer showed any advantage as they performed a series of tests designed to demonstrate their alertness. There was one difference noted in the caffeine group, though. Those who were both caffeinated and sleep-deprived rated themselves happier on the first two days, but more annoyed on the following days.
Crankiness and Stress
How do you feel after a night of poor sleep? Most people are familiar with the emotions that come with sleepiness. They can recall feeling cranky, easily angered, and more stressed out. That experience holds up in the laboratory, too. Sleep scientists have shown that going without adequate sleep can make you more sad, angry, stressed out, and emotionally exhausted.
This can turn into a vicious circle. It’s hard to fall asleep when you’re stressed. Stress makes you feel alert and awake, because it’s provoking your body to prepare for fight or flight. One study found that people with insomnia are 20 times more likely to develop panic disorder, which is one type of anxiety disorder. If you fear you may be in the midst of this cycle, the right mental health counselor can help address both your sleep problems and your mood.
Like stress and anxiety, depression is another condition closely associated with inadequate sleep. And like stress, depression can both cause and be caused by lack of sleep. One study showed that people with chronic insomnia stand a five-fold risk of developing depression. Another shows that as many as three out of four depressed patients have symptoms of insomnia, and that percentage could actually be higher.
Scientists have studied the brainwaves of depressed patients during sleep. They’ve found that a depressed person gets less REM sleep and tends to experience fragmented sleep more frequently than normal. Even after depression goes into full remission, sleep problems can remain, and when they do, this indicates a higher risk of relapse.
Poor Concentration and Memory Problems
Sleeplessness interferes with your memory, and can make concentration difficult. Memory is closely linked with two phases of sleep. REM sleep, which is the phase when dreams occur, is associated with your procedural memory. This is the memory you rely on for your know-how when you are learning a new task. Non-REM sleep is associated with declarative memory. That’s the memory you use when you have to recall an event or a fact. When sleep is disrupted, both types of memory are put at risk.
In addition, difficulty concentrating is linked with both fragmented sleep and insomnia. You may never realize it, though. Although studies show your concentration drops when you go without sleep, they also show that you are likely to rate your concentration higher during these times. This skewed self-perception may also be a consequence of poor sleep.
Feels Like a Cold
Hate to get sick? Better get your zzzs. Sleeping less than 6 hours a night has been shown to put you at greater risk of catching a cold and other illnesses. One study observed 164 healthy men and women over the course of a week. Most of the study participants were given nasal drops infected with rhinovirus, the virus that typically causes the common cold. About 30% wound up infected. Their sleep schedules were carefully monitored. It turned out that short sleepers were 4 times more likely to get sick than their well-rested peers. Another large study showed that women who sleep less than 6 hours per night are more likely to contract pneumonia.
This makes sense when you know how your immune system relies on sleep. Your production of T cells peaks at night while you sleep. T cells hunt down and destroy infections, and also support your body’s immune response in other ways. Other important immune cells are released into your body while you sleep, too, giving you extra protection to fight off disease. When you go without sleep for a prolonged period, your body is less capable of protecting itself from infection.
Paranoia and Hallucinations
Insomnia can bring on hallucinations and paranoia, and so can even mild sleep difficulties, although not as frequently. One survey found that your odds of a hallucinatory experience rise about 4% if you’ve had sleep difficulties over the past month. Those odds jump by about 8% if you suffer from chronic insomnia. These subjects did not suffer from other mental health disorders, although the presence of disorders like anxiety and depression increases the odds further. Another study found that more than half of people suffering from paranoia also experienced some level of insomnia.
Everything Hurts More
Everyone deals with pain from time to time. From joint pain and back aches to migraines and heartburn, pain is something that will appear in your life now and then. But whatever form of pain you find yourself in, it will likely be worse when you miss sleep.
Many studies have looked into the associations between sleep loss and pain. Together they’ve shown that sleep problems can lead to more headaches, higher risks of fibromyalgia and chronic pain, worsening arthritis pain and many other conditions. The association between bad sleep and increased pain is well established, but scientists still don’t know what causes it.
Sleep loss seems to increase inflammation as well, which is often painful. One of the problems is that sleeplessness can lead to obesity, and obesity has been shown to increase inflammation in turn. It’s a nasty cycle that takes work to reverse, but doing so could mean less pain throughout life.
You’re More Impulsive
What does it take to exercise self-control? Things like overspending, gambling, overeating, and addiction can ruin lives. But science isn’t sure how we can get a handle on these kinds of impulses. One theory is that you need a certain amount of energy in order to make better decisions. When you don’t get enough sleep, you don’t have as much energy either. Studies have tied poor sleep to teenage delinquency and other impulsive behaviors.
This could be a particularly difficult problem to control. After all, getting to bed at a reasonable hour is a good choice, and staying up late is often impulsive. So if you’ve already been sleeping poorly, it may be easier to make that type of poor, impulsive choice to stay up late before going to bed the next day.
It’s hard to keep your fine motor skills in tune without enough sleep. One study had doctors perform coordination tests after working a 24-hour call, and found that lack of sleep seriously hampered their ability to complete tasks correctly. Your hand-eye coordination suffers from drowsiness, too. In fact, people who are sleep-deprived do as bad or worse than intoxicated people in some tests.
Does your job rely on picking out visual details? If it does, you should make sure you’re in bed by bedtime. Studies show that you get worse at such tasks when sleep-deprived. Also, some types of sleep deprivation can harm what’s known as your visual working memory—that’s your brain’s ability to store pieces of visual information while at the same time filter out what you don’t need. With this critical piece of the visual puzzle impaired, you may find it more difficult than normal to receive instructions, to solve math problems in your head, and to avoid distraction.
Nodding Off While Driving
Drowsy driving is a serious problem, and the 70 million Americans suffering from a sleep disorder are having a frightening effect on the highway. One out of every 25 adult drivers admits to falling asleep while driving in the past 30 days. That means a lot of people on the road are getting such poor sleep that it is putting their lives, and the lives of those around them, in jeopardy.
Falling asleep at the wheel is of course very dangerous. But just being overly sleepy can be harmful too. It can slow your reaction time to dangerous situations. The national highway administration estimates that 72,000 crashes a year are caused by drowsy drivers, leading to an estimated 800 deaths. Medications that make you sleepy can make this serious problem even worse, so check the labels carefully and avoid driving after taking these prescriptions.
Low Sex Drive
It is possible that the sleep you’re not getting is affecting you in other ways within the bedroom. Your body produces testosterone when you sleep, especially during REM sleep. At the same time, testosterone levels dip while you’re awake. That’s true in both men and women, but men are more likely to suffer from sleep apnea. Sleep apnea has been linked to sexual problems such as erectile dysfunction, impotence, and low libido.
There’s another sleep problem that plays havoc in relationships, and perhaps it’s more familiar: snoring. Yes, it’s the fuel for a lot of jokes, but couples in which one partner snores are statistically less satisfied. Perhaps keeping your loved one from getting enough sleep brings sexual problems of its own.
Sleeplessness makes it harder for you to recognize if someone is happy, sad, or angry. One study had both well-rested and sleep-deprived subjects watch amusing and sad video clips. The sleep deprived group found the amusing clips less amusing, and the sad clips less sad. A different study asked another group of sleepy subjects and well-rested ones to recognize the emotions on photographed faces. Specifically the drowsy group found it harder to read the faces of happy and angry people, suggesting our ability to share the joy of others and to react to potentially threatening situations is hampered by inadequate rest.
Getting Back to Sleep
You’ve seen just how harmful to your health going without sleep can be. But for millions of people, getting enough sleep is frustratingly difficult. There are ways to get the recommended 7 to 9 hours of sleep every night, though, if you’re willing to put in some effort.
- Make a sleep schedule and keep to it. That means going to bed and waking up at the same time every night—yes, even on weekends.
- Create a good sleeping environment inside your bedroom. People sleep best when the room is dark, quiet, and cool. If ambient light is getting through your windows, the right curtains or tape can shut it out.
- Avoid naps, and particularly afternoon naps. These can further disrupt your sleep cycle and make it tough to fall asleep at bedtime.
- Staying active can help prepare your body to sleep. Intense workouts are best, but any additional activity helps.
- Make sure your mattress and pillow are comfortable. Pick a pillow that matches your own sleeping style.
- Get into a bedtime ritual. Doing the exact same things before you turn out the lights can remind your body that it’s time to go to bed.
Reviewed by Charles Patrick Davis, MD, PhD