Six Subtle Signs You're Not Getting Enough Sleep

Because it's not always obvious when your body needs more rest

By Alexandra Borda

Jul 17th, 2023

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It can be hard to know how much sleep you need. The Center for Disease Control has some general guidelines, which suggest that 18- to 60-year-olds need seven or more hours per night. However, there’s no magic formula for every person—and between social events, traveling, and work, most of us have experienced periods where we didn’t get enough shuteye.

Without enough rest, your body will often respond with obvious signs, such as feelings of fatigue throughout the day and excessive yawning. But it’s also possible that you might not even realize you’re just not getting enough sleep.

Here are six subtle signs to pick up on, so you can know if you need to make changes to your sleep routine.

Your skin breaks out.

The phrase “beauty rest” might have some truth behind it. Research shows that your skin goes through much of its restoration during the time you sleep. According to a study in Clinical and Experimental Dermatology, people who slept five hours or less had skin that was less moisturized and could not effectively protect and heal itself from exposure to ultraviolet light in comparison to those who slept seven or more hours a night. Therefore, frequent pimples or blackheads could be a sign you are not getting enough sleep. Other signals may include dark circles, swollen eyes, more wrinkles, and an overall sadder appearance.

You feel more irritable, or experience mood swings.

Have you ever felt upset when someone woke you up from a bad night’s sleep? Think back on that time when you stayed up binge-watching a TV show or working on a project to meet a deadline. Did you wake up feeling more grumpy and irritable the next day?

An increase in negative moods—such as anger, depression, irritability, and frustration—is a sign of not sleeping enough. Studies have confirmed this by identifying a two-way relationship between sleep and emotional brain function. The research shows that getting more sleep—particularly REM sleep—can help you better regulate and express your emotions throughout the day.

You’re gaining weight. 

There is evidence that sleep might be the missing factor for many people struggling to maintain or lose weight. According to a study on sleep deprivation and weight loss, consistently short sleep duration is a risk factor in weight gain and obesity.

When you don’t get enough sleep, your metabolism slows down, and food that is high in calories, carbohydrates, and fat is more appealing than usual. A lack of sleep can also lead to a loss in motivation to exercise, or cause you to feel more easily fatigued during physical activity.

You forget things.

While you sleep, your brain forms memories by processing information from the day. There are three parts to this memory formation: acquisition, consolidation, and recall. Acquisition is learning new information, and consolidation is when the brain takes in that information to make it a stable memory, which you will later recall.

Lack of sleep can disrupt that cycle by negatively affecting our ability to acquire information throughout the day, and also our time to process it overnight. This can lead to forgetfulness—not only are you having more difficulty absorbing information throughout the day due to increased tiredness and difficulty focusing, but you’re also not spending as much time filing it away.

You wake up groggy.

The sound of an alarm clock is not something that many people enjoy waking up to. We’ve all wanted to hit snooze and go back to dreaming about our ideal vacation. Although occasional morning grogginess is normal, the constant desire to fall back asleep can be a sign of not getting enough sleep, as can temporary disorientation after initially waking up.

You can’t live without caffeine.

Have you ever woken up late and needed an instant energy boost? Maybe you stop at your local coffee shop and grab a quick iced coffee for a pick-me-up before you head to work or school. Then, during your lunch break, a feeling of fatigue begins to creep back in and you start looking for the vending machine.

Although caffeine may help us stay alert and awake temporarily, a study by the Journal of Clinical Sleep Medicine found that ingesting 400 mg of caffeine fewer than six hours before going to bed significantly disrupts sleep. Even taken six hours before bed, caffeine reduces the amount of sleep by one hour. This amount of sleep loss, experienced over several nights, might have effects on daytime function—which can then cause you to reach for more caffeine.

Final Thoughts

Although it might be tempting to sacrifice your slumber to check things off your to-do list, remember that good sleep matters. Take note of the signs that you are not getting enough sleep, but try not to stress—everyone has sleepless nights or exhausted mornings after multiple snoozed alarms. With a little time and effort, your sleep can get better. Check out our tips for better sleep for more.


What happens when you don’t get enough sleep?

Sleep deprivation can have both short-term and long-term effects. Short-term effects can include reduced sex drive, anxiety and depression, moodiness, clumsiness, learning and memory impairments, slower reaction times, and increased appetite with carbohydrate cravings.

Sustained lack of sleep can have more serious consequences on your health. Long-term effects associated with sleep deprivation might include diabetes, heart attack, heart failure, or stroke. Other issues that may arise are depression, anxiety, reduced immune system, and obesity.

How do I know how much sleep I need?

We’ve all heard the old rule that you need at least seven hours of sleep per night. Yet, newer research indicates that as we age, the amount of sleep we need changes. Young adults from the ages of 18–25 are recommended to sleep seven to nine hours per night, as are adults ages 26–64. Yet, six to 10 hours may be appropriate for adults from 26–64, in comparison to the six to 11 hours for young adults from 18–25. For adults from 65 and older, the recommended hours of sleep per night changes to seven to eight hours.

How do I change my sleep habits? 

If you are looking to fall asleep easier, or stay asleep throughout the night, check out these 21 tips to sleep better. You don’t need to make huge, immediate changes to your life or schedule. Small things, like journaling before bed, avoiding blue light before you want to fall asleep, and going to bed around the same time every night are simple things you can do now to improve your sleep.