Sleep is essential for refreshing and rejuvenating the body and the mind. If we fail to get enough sleep, it can adversely affect our mental and physical health. The amount of sleep one needs can vary considerably depending on one's age. In general, children need more sleep than adults.
The whole body - the nervous, immune, and the skeletal system - gets rejuvenated when we sleep. An inability to sleep properly, or insomnia, is known to increase the risk of weight gain, high blood pressure, and diabetes.
Though the importance of sleep is not lost on everyone, not many people know how much sleep they actually need. The amount of sleep one needs depends on a wide range of factors, including the age of the individual, genetics, and the level of activity.
For example, the amount of sleep a child needs can be quite different from that of an adult or elderly individual. In general, as we age, we tend to require less sleep.
How Much Sleep Do Children Need?
Children need to sleep more than adults. Usually, newborns need somewhere around 12 to 18 hours of sleep daily.
However, they don't sleep continuously for 12 to 18 hours, as hunger often wakes them up. At a stretch, newborns can sleep for 3 to 4 hours. They usually do not have a definite sleep pattern. You may observe a pattern in their sleeping after the age of 3 months.
Infants in the age group of 3 to 11 months need to sleep for 14 to 15 hours on an average. As they grow, the amount of sleep they need gradually decreases. Typically, a toddler (1 to 3 years old) sleeps for 12 to 14 hours, while preschoolers tend to sleep for about 11 to 13 hours.
By the time children reach the age of 5 years, they need 10 to 11 hours of sleep on an average until they become 10 years old. Teenagers, on the other hand, need about 8 to 9 hours of sleep daily.
How Much Sleep Do Adults Need?
There is no hard and fast rule regarding the amount of sleep an adult needs. As a thumb rule, it is considered that adults need about 7 to 9 hours of sleep daily. But it has been observed that some adults are just fine with 5 to 6 hours of sleep as well.
On the other hand, some adults need 10 to 11 hours of sleep to feel fresh and energetic throughout the day, and perform their daily activities effectively. So, it is better to try to know the amount of sleep you need on your own.
To determine the amount of sleep you need, you need to take two things into consideration - the 'basal sleep need' and 'sleep debt'. Basal sleep can be termed as the amount of sleep we require on a regular basis. If we fail to meet our basal sleep need, the amount of sleep lost gets accumulated and this is known as 'sleep debt'.
The basal sleep need is said to be 7 to 8 hours. But some may experience sleepiness and fatigue even after sleeping 7 to 8 hours continuously for a few nights. The reason for this could be sleep debt, which can cause one to feel sleepy and less alert even after sleeping 7 to 8 hours at night. One may need some extra sleep to pay off the 'sleep debt'.
The sleep pattern in humans is governed by the circadian rhythm, which can be considered a biological clock. The circadian rhythm is concerned with the repetition of certain biological functions like sleeping and waking at regular intervals.
To know how much sleep you need, first of all you have to stick to a fixed sleeping schedule for a few weeks. Decide a fixed time for going to the bed, and then allow yourself to sleep as long as you want. Do not use the alarm clock to wake you up in the morning.
Otherwise, you can set a fixed wake-up time in the morning, and then go to your bed whenever you feel sleepy and tired. Continue either of these two methods for 2 to 3 weeks, in order to find out the amount of sleep you actually need.
While trying to figure out the amount of sleep you need, it is equally important to take into account the quality of sleep. If the quality of sleep is good, then you wake up feeling alert and refreshed.
On the other hand, if the quality of sleep is poor, you can wake up feeling still sleepy, irritable, and listless. So, how one feels after waking up is an important indicator of whether he or she is getting enough quality sleep during the night.
If you consistently feel that you are not getting enough sleep at night, then take it seriously, and have a talk with your physician, as you might be suffering from sleep disorders. Your physician can help you find out some ways to sleep better, and identify and address the underlying problems.