Is Five Hours Of Sleep Enough? Here’s What The Experts Say.
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Somewhere along the way, spending more time “hustling” and less time sleeping became a badge of honor. Ask anyone in the throes of building a business or making a name for themselves, and you’ll likely hear that days and nights full of work — and little sleep — are the norm. And while we’re not one to get in the way of anyone putting in the work to build their empire, it’s worth asking, “is five hours of sleep enough?” Well, our expert says, not quite.
Is Five Hours of Sleep Enough?
Terry Cralle, MS, RN, and clinical sleep health educator, says, “Most adults require 7-9 hours of sleep a night, so, no, five hours of sleep is not enough.”
While Cralle points out that there’s a small segment of the population with a genetic variant that allows them to function well on very little sleep, she notes that those folks only amount to maybe 1 percent of the population and, by definition, are a rare breed. (1) These “short sleepers feel alert and refreshed and function normally after regularly getting less than 6 hours of sleep,” says Cralle, but that’s not the case for most of us.
For the rest of us who don’t have that superpower, Cralle says “people cannot ‘learn’ to get by on less sleep than needed or acclimate to chronic sleep debt.”
The Recommended Amount of Sleep by Age
The amount of sleep a person needs can vary widely by age — take a look at the graphic below to better understand the sleep needs of everyone in your household.
The Importance of Getting Enough High-Quality Sleep
While we know that it’s important to meet our daily sleep requirements, your sleep quality also matters. Quality sleep can improve your mood and cognition, and do some pretty heavy lifting for your overall physical health.
Improved Immune Health and Function
If you’re getting plenty of quality sleep each night, you might not get sick as often. And the science here is easy enough — sleep supports immune function. While scientists once thought that sleep was purely passive, research has revealed a host of biological housekeeping going on behind the scenes.
Your body ramps up its production of some hormones while throttling back on the production of others. More specifically, cortisol, epinephrine, and norepinephrine decrease while your growth hormone (GH), leptin, and prolactin levels increase. Those hormones, in turn, all work to support immune cell activation, ultimately boosting your defenses against inflammation and infection. (3)
Healthy Weight Management
If you’re tired of battling the bulge, you might try logging a few more hours of sleep each night. One study showed that participants who clocked a few more hours of shut-eye each night had a lower body mass index than those who regularly slept less than 6.5 hours per night. At the same time, another linked longer sleep duration to reduced calorie intake. We could go on, but you get the idea. (4) (5)
Reduced Risk for Diabetes, Stroke, and Heart Disease
By lowering your blood pressure and exerting some control over your blood sugar, high-quality sleep in adequate amounts can reduce your risk of diabetes, stroke, and heart disease. (6)
It’s common knowledge that a good night’s sleep is a good cure for what ails you, especially when you’re stressed. And it’s not in your head: Research shows high-quality sleep can go a long way towards reducing your stress. But we should note here that stress and sleep share a bidirectional relationship — stress can meddle with your ability to sleep, and your lack of sleep can cause stress. (7)
Improved Mood, Memory, and Cognitive Function
In addition to keeping your stress in check, adequate amounts of high-quality sleep can profoundly impact your emotions and cognitive function. And you don’t have to take our word for it. Study after study shows that optimistic people sleep longer and better. (8) (9)
The Effects of Getting Five Hours of Sleep
As we noted earlier, most adults need at least seven hours of sleep per night. Any less for prolonged periods, and you’ll likely find yourself on the road to sleep deprivation, which comes with its own issues. (11) (12) (13)
Over the short term, sleep deprivation can lead to:
- Difficulty concentrating
- Poor cognitive functioning
- Impaired memory
- Increased likelihood of accidents due to drowsy driving
- Poor judgment/decision-making
Over the long term, getting five hours of sleep per night can lead to more severe and chronic health conditions, including:
- High blood pressure
- Heart attack
- Heart disease
Cralle adds that just as quality sleep can boost your immunity, short sleep can impede your body’s ability to fight off invaders. Specifically, Cralle points to a host of studies linking short sleep with impaired anti-tumor response and an increased risk for breast, colorectal, and prostate cancer. Cralle also directs our attention to a data analysis showing that sleeping less than five hours a night may increase our mortality risk (from all causes) by about 15 percent. (14) (15)
Is It Normal to Wake Up Tired?
While a bit of sleep inertia may be common, Cralle says it’s “not normal to wake up tired” – at least not on a regular basis. Sleep is a crucial pillar of health, and if you’re doing it right, you should wake up refreshed and rested.
“It’s important to be consciously aware of your sleep beliefs, attitudes, and habits,” says Cralle. “Step back and look at how sleep, or the lack of it, is affecting you. Too many people see sleep as a luxury and don’t fully grasp that sleep is a basic, yet often disregarded, biological need.”
If you regularly wake up feeling tired and are ready for some self-reflection, Cralle shares the following questions/thought starters.
- Do you have a consistent bedtime and wake time?
- Are you scheduling sufficient sleep every day of the week (not undersleeping during the week in hopes of oversleeping on the weekends)?
- Do you repeatedly hit the snooze button in the morning? (Don’t do that — rather, set your alarm for the latest wake-up time and then get out of bed).
- What time did you go to bed?
- Did you fall asleep within 15 – 20 minutes of laying down, or do you toss and turn for a while?
- Are you waking up during the middle of the night and having trouble getting back to sleep?
Some of the behaviors that lead to sleepy wake ups are correctable, but if your tiredness has more to do with not being able to sleep, it may be worth having a conversation with your doctor.
Why Can’t I Sleep?
The reasons for missing out on sleep vary from person to person. For some people, ongoing health issues may hinder their shut-eye, while others may skirt their sleep as a result of lifestyle choices. “For some, the fear of missing out on something important keeps us from hitting the sack when we should, while others are lured by electronics,” says Cralle. “Some people may suffer because they’re not working with their chronotype, and some simply don’t understand the benefits of prioritizing sleep.”
This shouldn’t come as a surprise to anyone, but it bears repeating. The things you do and eat during the day can affect your ability to get the sleep you need. If heavy meals, alcohol, or caffeine make frequent appearances in your diet, you might consider making some changes for the sake of your sleep — while you don’t have to eliminate them completely, you should think about cutting those sleep stealers off earlier in the day. (15) (16)
And if you find that sleep doesn’t come easy most nights, a sedentary lifestyle could be the issue too. A tired body tends to sleep more easily, so it might be time to get up and get moving. (17)
Poor Sleep Hygiene
Good sleep hygiene is a crucial part of a good night’s sleep. And while the term may be strange to some, sleep hygiene isn’t as complex as it sounds — you might think of it as a bedtime/sleep routine.
The most important aspects of sleep hygiene are:
- Maintaining a consistent sleep and wake schedule
- Keeping your sleep environment cool, dark, and quiet
- Reserving your bed for sleep and sex only
- Establishing a calming bedtime routine
- Eliminating screens and devices at least one hour before bed
We’re all spinning a lot of plates, but if your “plates” leave you feeling overwhelmed, you might consider speaking with a therapist to help you manage your stress. The thing to remember here is that stress can stymie your sleep, and low-quality fragmented sleep can lead to stress. (7)
With work schedules that don’t sync with the sun, night shift workers are prime candidates for short sleep and sleep deprivation. While there’s probably little you can do to change your schedule, you can double down on your sleep hygiene to help you sleep better on the night shift. (19) (20)
Prolonged periods of short sleep could be a sign of a sleep disorder. If you find that you’re getting five hours of sleep (or less) per night regularly, it might be time to speak with your doctor to rule out insomnia, sleep apnea, or any other sleep disorders on the spectrum, including restless leg syndrome and narcolepsy.
How to Get More Sleep
“Sleep should be managed as thoughtfully and deliberately as we manage our daytime schedules and activities,” says Cralle. “Sufficient sleep should not be viewed as an indulgence or luxury, and we should be proactive about our sleep needs.”
To get more sleep, Cralle suggests:
- Making sufficient sleep a daily priority; schedule your day/night around it (rather than the other way around)
- Setting an alarm for bedtime so you don’t stay up later than planned
- Having a calming and relaxing bedtime routine
- Keeping a gratitude journal — jot down three good things about your day each night before you go to bed. Focusing on positive things should put you in a more positive mindset, which is good for sleep
- Getting natural light in the mornings
- Getting daily exercise
Cralle notes, “If you adopt healthy sleep habits and allow time for sufficient sleep but still don’t feel well-rested, it might be time to see a sleep specialist — better yet, take the initiative to address sleep at every healthcare provider encounter.”
Do some people only need 5 hours of sleep?
A small portion of the population is born with a genetic variant that allows them to function well on very little sleep. Accounting for less than 1 percent of the population, these short sleepers feel alert and refreshed after regularly getting less than six hours of sleep.
Why do I feel energized with less sleep?
You might feel more energized with less sleep because you’re essentially tired and wired. Italian neurophysiologist and researcher Marcello Massimini once showed that a tired brain reacts to stimuli with strong spikes of energy. (21)
How much sleep should an adult get?
The American Academy of Sleep Medicine recommends that adults get seven or more hours of sleep per night.
The Last Word From Sleepopolis
While getting plenty of high-quality sleep can be a boon to your physical and mental health, a good swath of the population regularly falls short of their requirements. Sufficient sleep is crucial for optimal health, and whether it’s intentional or not, sleep deprivation can lead to a host of health concerns over the short term and more serious health issues over the long term.
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- Terry Cralle, MS, RN. Email Communication. August 7, 2023.