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What is sleep?
Sleep is a period of unconsciousness during which your brain and body functions stay active. It is a complex biological process that helps people process new information, stay healthy, and feel rested.
During sleep, the brain will cycle through five different phases: stage 1, 2, 3, 4, and rapid eye movement (REM) sleep. Each stage of sleep is linked to a specific type of brain waves (patterns of electrical activity in the brain). You need certain phases of sleep to help you
Feel rested and energetic the next day
Learn information, get insight, and form memories
Give your heart and vascular system a rest
Release more growth hormone, which helps children grow. It also boosts muscle mass and the repair of cells and tissues in children and adults.
Release sex hormones, which contributes to puberty and fertility
Keep you from getting sick or help you get better when you are sick, by creating more cytokines (hormones that help the immune system fight various infections)
How much sleep do I need?
The amount of sleep you need depends on several factors, including your age, lifestyle, health, and whether you have been getting enough sleep recently. The general recommendations for sleep are
Newborns: 16-18 hours a day
Preschool-aged children: 11-12 hours a day
School-aged children: At least 10 hours a day
Teens: 9-10 hours a day
Adults (including the elderly): 7-8 hours a day
During puberty, teenagers' biological clocks shift, and they are more likely to go to bed later than younger children and adults, and they tend to want to sleep later in the morning. This delayed sleep-wake rhythm conflicts with the early-morning start times of many high schools and helps explain why most teenagers do not get enough sleep.
Some people think that adults need less sleep as they age. But there is no evidence to show that seniors can get by with less sleep than people who are younger. As people age, however, they often get less sleep or they tend to spend less time in the deep, restful stage of sleep. Older people are also more easily awakened.
And it's not just the number of hours of sleep you get that matters. The quality of the sleep you get is also important. People whose sleep is frequently interrupted or cut short might not get enough of certain stages of sleep.
If you are wondering whether you are getting enough sleep, including quality sleep, ask yourself
Do you have trouble getting up in the morning?
Do you have trouble focusing during the day?
Do you doze off during the day?
If you answered yes to these three questions, you should work on improving your sleep.
What are the health effects of not getting enough sleep?
Sleep is important for overall health. When you don't get enough sleep (sleep deprivation), it does more than just make you feel tired. It can affect your performance, including your ability to think clearly, react quickly, and form memories. This may cause you to make bad decisions and take more risks. People with sleep deprivation are more likely to get into accidents.
Sleep deprivation can also affect your mood, leading to
Problems with relationships, especially for children and teenagers
Not getting enough sleep can also mean that you don't get enough of the hormones that help children grow and help adults and children build muscle mass, fight infections, and repair cells.
Sleep deprivation magnifies the effect of alcohol. A tired person who drinks too much alcohol will be more impaired than a well-rested person.
How can I get better sleep?
You can take steps to improve your sleep habits. First, make sure that you allow yourself enough time to sleep. With enough sleep each night, you may find that you're happier and more productive during the day.
To improve your sleep habits, it also may help to
Go to bed and wake up at the same time every day
Avoid caffeine, especially in the afternoon and evening
Exercise regularly, but don't exercise too late in the day
Avoid alcoholic drinks before bed
Avoid large meals and beverages late at night
Don't take a nap after 3 p.m.
Relax before bed, for example by taking a bath, reading or listening to relaxing music
Keep the temperature in your bedroom cool
Get rid of distractions such as noises, bright lights, and a TV or computer in the bedroom. Also, don't be tempted to go on your phone or tablet just before bed.
Get enough sunlight exposure during the day
Don't lie in bed awake; if you can't sleep for 20 minutes, get up and do something relaxing
See a doctor if you have continued trouble sleeping. You may have a sleep disorder, such as insomnia or sleep apnea. In some cases, your doctor may suggest trying over-the-counter or prescription sleep aid. In other cases, your doctor may want you to do a sleep study, to help diagnose the problem.
If you are a shift worker, it can be even harder to get a good sleep. You may also want to
Take naps and increase the amount of time available for sleep
Keep the lights bright at work
Limit shift changes so your body clock can adjust
Limit caffeine use to the first part of your shift
Remove sound and light distractions in your bedroom during daytime sleep (for example, use light-blocking curtains)
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