What Sleep Is and Why All Kids Need It - Hazli Collection

What Sleep Is and Why All Kids Need It

As we drift off to sleep, our body begins its night-shift work:

  • healing damaged cells
  • boosting your immune system
  • recovering from the day’s activities
  • recharging your heart and cardiovascular system for the next day

Sleep plays a vital role in good health and well-being throughout our life.


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.

Studies show that a good night's sleep improves learning. Whether you're learning math, how to play the piano, how to perfect your golf swing, or how to drive a car, sleep helps enhance your learning and problem-solving skills. Sleep also helps you pay attention, make decisions, and be creative, says U.S. Department of Health & Human Services.

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, and coping with change. Sleep deficiency also has been linked to depression and risk-taking behavior.

Children and teens who are sleep deficient may have problems getting along with others. They may feel angry and impulsive, have mood swings, feel sad or depressed, or lack motivation. They also may have problems paying attention, and they may get lower grades and feel stressed.

But how is sleep related to physical health?

Did you know that sleep is involved in healing and repair of your heart and blood vessels? Ongoing sleep deficiency is linked to an increased risk of heart disease, kidney disease, high blood pressure, diabetes, and stroke.

Sleep makes the child thinner! 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 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 makes your child taller!

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.

With enough sleep, the child is rarely sick!

The immune system relies on sleep to stay healthy. Ongoing sleep deficiency can change the way in which your immune system responds. For example, if the sleep deficient, we might have trouble fighting even common infections.

What are the sleep cycles?

Stage 1

is light sleep where you drift in and out of sleep and can be awakened easily. In this stage, the eyes move slowly and muscle activity slows. During this stage, many people experience sudden muscle contractions preceded by a sensation of falling.

STAGE 2

In stage 2, eye movement stops and brain waves become slower with only an occasional burst of rapid brain waves. The body begins to prepare for deep sleep, as the body temperature begins to drop and the heart rates slows.

STAGE 3

When a person enters stage 3, extremely slow brain waves called delta waves are interspersed with smaller, faster waves. This is deep sleep. It is during this stage that a person may experience sleepwalking, night terrors, talking during one’s sleep, and bedwetting. These behaviors are known as parasomnias, and tend to occur during the transitions between non-REM and REM sleep.

STAGE 4

In stage 4, deep sleep continues as the brain produces delta waves almost exclusively. People roused from this state feel disoriented for a few minutes.

STAGE 5: REM

What Is REM stage?

Usually, REM sleep happens 90 minutes after you fall asleep. The first period of REM typically lasts 10 minutes. Each of your later REM stages gets longer, and the final one may last up to an hour. Your heart rate and breathing quickens.

If deep sleep is about body, REM is about the brain, because brain is very active during REM sleep, yet the body is very inactive. Actually, it’s so inactive, you’re actively paralyzed during REM sleep.

REM is when most dreaming happens and your eyes move rapidly in different directions (hence the name). Heart rate increases and your breathing becomes more irregular.

REM is very important for emotion regulation and memory—you’re clearing the brain of things that aren’t needed. It’s also the peak of protein synthesis at the cellular level, which keeps many processes in the body working properly.

Did you know that babies can spend up to 50% of their sleep in the REM stage, compared to only about 20% for adults.

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