Sleep plays a vital role in good health and wellbeing throughout your life. Getting enough quality sleep at the right times can help protect your mental health, physical health, quality of life and safety.
The way you feel while you're awake depends in part on what happens while you're sleeping. During sleep, your body is working to support healthy brain function and maintain your physical health. In children and teens, sleep also helps support growth and development.
The damage from sleep deficiency can occur in an instant (such as a car crash), or it can harm you over time. For example, ongoing sleep deficiency can raise your risk for some chronic health problems. It also can affect how well you think, react, work, learn and get along with others.
Healthy brain function and emotional wellbeing
Sleep helps your brain work properly. While you're sleeping, your brain is preparing for the next day. It's forming new pathways to help you learn and remember information.
Studies show that a good night's sleep improves learning. Whether you're learning math, how to play the piano or how to perfect your golf swing, sleep helps enhance your learning and problem-solving skills. Sleep also helps you pay attention, make decisions and be creative.
Studies also show that sleep deficiency alters activity in some parts of the brain. If you're sleep deficient, you may have trouble:
Making decisions
Solving problems
Controlling your emotions and behavior
Coping with change
Sleep deficiency also has been linked to depression, suicide and risk-taking behavior.
Children and teens who are sleep deficient may:
Have problems getting along with others
Feel angry and impulsive
Have mood swings
Feel sad or depressed
Lack motivation
Have problems paying attention
Get lower grades
Feel stressed
Physical health
A common myth is that people can learn to get by on little sleep with no negative effects.
Sleep plays an important role in your physical health. For example, sleep is involved in the healing and repair of your heart and blood vessels.
Sleep deficiency also increases the risk of obesity. For example, one study of teenagers showed that with each hour of sleep lost, the odds of becoming obese went up. Sleep deficiency increases the risk of obesity in other age groups as well.
Sleep helps maintain a healthy balance of the hormones that make you feel hungry (ghrelin) or full (leptin). When you don't get enough sleep, your level of ghrelin goes up and your level of leptin goes down. This makes you feel hungrier than when you're well-rested.
Sleep also affects how your body reacts to insulin, the hormone that controls your blood glucose (sugar) level. Sleep deficiency results in a higher-than-normal blood sugar level, which may increase your risk for diabetes.
Sleep also supports healthy growth and development. Deep sleep triggers the body to release the hormone that promotes normal growth in children and teens. This hormone also boosts muscle mass and helps repair cells and tissues in children, teens and adults. Sleep also plays a role in puberty and fertility.
Your immune system relies on sleep to stay healthy. This system defends your body against foreign or harmful substances. Ongoing sleep deficiency can change the way in which your immune system responds. For example, if you're sleep deficient, you may have trouble fighting common infections.
Sleep deficiency is linked to many chronic health problems, including:
Heart disease
Kidney disease
High blood pressure
Diabetes
Stroke
Obesity
Depression
Sleep deficiency can lead to physical and mental health problems, injuries, loss of productivity, and an even greater risk of death.
How much sleep is enough?
The amount of sleep you need each day will change over the course of your life. In general, here is what is recommended:
Toddlers (1–2 years): 11–14 hours, including naps
Preschool (3–5 years): 10–13 hours, including naps
School-age (6–13 years): 9–12 hours
Teens (14–17 years): 8–10 hours
If you routinely lose sleep or choose to sleep less than needed, the sleep loss adds up. The total sleep lost is called your sleep debt. For example, if you lose 2 hours of sleep each night, you'll have a sleep debt of 14 hours after a week.
Some people nap as a way to deal with sleepiness. Naps may provide a short-term boost in alertness and performance. However, napping only provides some of the other benefits of night-time sleep. Thus, you can't really make up for lost sleep.
Bad sleep habits and long-term sleep loss will affect your health. If you're worried about whether you're getting enough sleep, try using a sleep diary for a couple of weeks.
Write down how much you sleep each night, how alert and rested you feel in the morning, and how sleepy you feel during the day. Show the results to your doctor and talk about how you can improve your sleep.
Sleeping when your body is ready to sleep also is very important. Sleep deficiency can affect people even when they sleep the total number of hours recommended for their age group.
Tips for getting enough sleep
Make sure that you allow yourself enough time to sleep. Sleep often is the first thing that busy people squeeze out of their schedules. Making time to sleep will help you protect your health and wellbeing now and in the future.
To improve your sleep habits, it also may help to:
Go to bed and wake up at the same time every day. Have a set bedtime and a bedtime routine.
Try to keep the same sleep schedule on weeknights and weekends. Limit the difference to no more than about an hour. Staying up late and sleeping in late on weekends can disrupt your body clock's sleep-wake rhythm.
Use the hour before bed for quiet time. Avoid strenuous exercise and bright artificial light, such as from a TV or computer screen. The light may signal the brain that it's time to be awake.
Avoid heavy and/or large meals within a couple of hours of bedtime. Having a light snack is okay.
Avoid caffeine (including caffeinated soda, coffee, tea and chocolate).
Spend time outside every day (when possible) and be physically active.
Keep your bedroom quiet, cool and dark (a dim night light is fine if needed).
Take a hot bath or use relaxation techniques before bed.
Napping during the day may provide a boost in alertness and performance. However, if you have trouble falling asleep at night, limit naps or take them earlier in the afternoon.
Source: NIH
