Factors that control sleep

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teen boy sleeping

Sleep is a very important state of rest and recharging. Your body needs a certain amount of sleep to function at its best. At night while you’re asleep, your brain files and stores what you learned and experienced during the day and your body grows, heals and recovers.

Humans and animals alike have regular rest and activity patterns. An average person spends about a third of their life sleeping. A baby sleeps about 16 hours a night, but as you get older, you need less sleep. Generally, a teen or young adult usually needs to sleep eight to nine hours a night.

People who don't sleep well often feel tired, less energetic, irritable and more sensitive to pain during the day. Research studies show that not getting enough sleep makes people feel pain more strongly and makes them more likely to have headaches and even widespread body pain the next day.

​​Different factors regulate or control your sleep.

The circadian clock (from the Latin roots circa = about and diem = day) is your body’s internal clock. This controls the timing of your sleep patterns.

Thanks to the circadian clock, we feel sleepy at night and awake during the day. Usually, the longer you stay awake, the stronger your desire to sleep. This need to sleep is called your homeostatic sleep drive. We sleep best when we keep our clock on a stable rhythm. This is why healthy sleep routine tips encourage going to bed and waking up at the same time every day.

Chemicals in your brain, called neurotransmitters, are involved in making you feel sleepy or awake. One such neurotransmitter is called adenosine. This plays a very important role in controlling how sleepy you feel. Without enough adenosine, it’s difficult for our bodies to reach the deepest parts of our sleep cycle. Deep sleep is very important because it’s the time when muscles repair themselves and the body secretes growth hormone.

Your brain also produces a hormone, melatonin, to help control your circadian clock. Normally, the amount of melatonin in your body begins to increase in the mid- to late evening. It remains high for the most of the night and then drops to a lower level in the morning.

Light is also very important in controlling your sleep because it affects the amount of melatonin that your body produces. Increasing light exposure in the morning and decreasing light exposure at night can help to improve your sleep. Decreasing light exposure at night also means limiting your “screen time” (time spent using TVs, computers, smartphones and so on) in the hour or two before bed.

During the winter months, when the days are shorter, your body may produce melatonin either earlier or later in the day than usual. This change can lead to changes in your sleep patterns. Many people who live in northern countries such as Canada can be affected by seasonal problems with their sleep because they are exposed to very little light during the winter months. Talk to your healthcare team if you think this might be an issue for you.

Last updated: May 2nd 2016