How Much Sleep Do Adults Need on an Average Night to Feel Rested?

Sleep Needs Based in Genetics, Change with Aging

Sleep needs vary based on genetics, age, activity, and other factors, but not getting enough may leave you feeling sleep deprived
Sleep needs vary based on genetics, age, activity, and other factors, but not getting enough may leave you feeling sleep deprived. Getty Images

If you experience excessive daytime sleepiness, you may not be getting enough sleep. How much sleep do adults need on an average night to feel rested? Learn how sleep needs change as we become older and whether or not you are getting enough to feel rested. Finally, consider other factors that might affect sleep quality, even if you are getting sufficient hours of shuteye in bed.

What Factors Determine the Amount of Sleep You Need?

The amount of sleep that you need is likely determined by your genetics, your age, your overall health, the various demands during your day, and other factors.

Some people require more sleep and others get by on less. As we get older, we may have decreased ability to sleep at night, resulting in more time in lighter sleep and increased insomnia. Medical problems, including chronic pain and other sleep disorders like sleep apnea, may impact the ability to sleep at night. Increased or decreased physical activity, including exercise, may also impact sleep needs.

If you obtain the total amount of sleep that you need to feel rested, you can avoid the impacts of sleep deprivation and improve your daytime function. Most people get most of their sleeping done at night, but sleep needs can also be supplemented by taking naps. It is possible to determine the approximate amount of sleep you need by following a simple experiment.

What Are the Average Sleep Needs for Adults?

In general, the average healthy adult needs 7 to 9 hours of sleep per night. Experiments have demonstrated that the average amount of sleep needed to avoid detrimental effects on daytime function is about 8 hours and 10 minutes.

It is recommended that adults beyond age 65 may need less sleep, averaging 7 to 8 hours instead. If excess time is spent in bed, insomnia will result.

This normal distribution of sleep needs in a population is a bell-shaped curve. Just like height, weight, intelligence, and other factors: there are people at the extremes and you may not fit the "average." Some individuals may only need 6 hours of sleep to wake feeling completely rested without adverse consequences.

Extended time spent in bed for these individuals would result in insomnia. On the other hand, some people may need 9 hours (or even more), and only getting 8 hours of sleep will result in sleep deprivation.

If you find yourself feeling sleepy during the day, you may not be getting enough sleep. Try to keep a regular bedtime and a fixed wake time. Go to bed when you feel sleepy, and try to meet your individual sleep needs by protecting your sleep time from other activities. When waking in the morning, try to get 15 to 30 minutes of sunlight exposure either upon awakening or at sunrise.

The Consequences of Inadequate Sleep

If you get less sleep than you need, you are likely to begin accumulating a sleep debt. You may have sleep deprivation, which can result in physical as well as psychological effects. If you are chronically sleep deprived, you may suffer from adverse health consequences like obesity.

In some cases, it is not solely the total hours that is important. Sleep quality can be severely undermined by conditions like obstructive sleep apnea and periodic limb movements of sleep.

If you get enough hours of sleep, but still don't wake feeling rested or have sleepiness later in the day, you should speak with a sleep doctor about other factors that might be impacting the quality of your sleep.


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