Why Is Sleep Needed?
At one point, sleep was understood to be a point in the day in which our bodies and brain “shut off,” but we now understand that many functions and processes require sleep.
There is no consensus about why exactly we need to sleep, but we do know sleep plays a critical role in our overall health and well-being. There are three main areas in which we know sleep benefits us:
Restoration and Rejuvenation
During the night sleep restores the body’s energy supply, which gets depleted as we complete activities of daily living throughout the day.
Our body tissues also have an opportunity to be restored while we sleep.
Learning and Memory
Rest helps to give you the energy you need to pay attention and concentrate as you learn new tasks during the day.
In addition, sleep is believed to be the time in which the brain consolidates memories, which makes learning new things easier.
The body produces cytokines, which are special proteins that enable the immune system to fight off infection.
Scientists believe that the body creates more cytokines during periods of sleep when people are sick, which would explain why people feel tired when they are sick.
It is the body’s natural way of letting you know that it needs time to produce these proteins to strengthen the immune system.
How Many of Hours of Sleep Are Needed?
According to the Centers for Disease Control and Prevention (CDC), your sleep needs change as you age. Broken down by age group, the recommended hours of sleep per day are as follows:
- Newborn (0-3 months) – Between 14 and 17 hours
- Infant (4-12 months) – Between 12 and 16 hours
- Preschool (2-5 years) – Between 10 and 13 hours
- School Age (6-12 years) – Between 9 and 12 hours
- Teenager (13-18 years) – Between 8 and 10 hours
- Adult (18-60 years) – At least 7 hours
- Older Adult (61-64 years) – Between 7 and 9 hours
- Elderly Adults (65+ years) – Between 7 and 8 hours
What is Circadian Rhythm?
Ever wonder why people typically sleep at night and are awake during the day? The circadian rhythm is the natural, 24-hour cycle our bodies follow.
This cycle is influenced by factors like lightness, darkness, genetic makeup, and hormones that are released to prompt sleep. Abnormalities in the circadian rhythm, such as working a night shift, can lead to sleep disorders.
Stages of Sleep: REM and Non-REM Cycles
Your body cycles between two different types of sleep throughout the night – rapid eye movement (REM) sleep and non-REM sleep. Within the non-REM cycle there are three phases:
During stage 1 of non-REM sleep, which lasts about 5 to 10 minutes, the eyes are closed but you can easily wake up.
Stage 2 of non-REM sleep is light sleep, and during this stage your heart rate dips and your body temperature lowers as you get ready for deep sleep.
Stage 3 of non-REM sleep is deep sleep. It is harder to wake a person up when they are in deep sleep, and if they do wake up they are typically dazed and confused for a couple of minutes. The body repairs and regrows tissue and bones during deep sleep.
Meanwhile, REM sleep usually occurs about an hour and a half after you initially fall asleep. You heart rate and breathing speed up, and you are most likely to have intense dreams during this sleep cycle due to higher levels of brain activity.
Adults spend about 20% of their sleep in the REM cycle, while babies can spend up to 50% of their sleep in that stage.
What Are Dreams?
Dreams are the stories and images created by the brain while a person sleeps. Possible explanations for why dreams occur include:
- Dreams are the manifestation of our unconscious desires and wants
- The brain interprets random signals from the body while sleeping
- Information processed during the day manifests as a dream
- Dreams work as a form of psychotherapy
- Scientists believe that 95% of any dreams that happen through the night are forgotten by the time a person gets out of bed.
- Health Consequences of Poor Sleeping Habits
Not sleeping well can wreak complete havoc on your whole body – with effects ranging from mild and annoying to life-threatening.
Some health consequences include:
- Lowered brain ability and activity
- Lower immunity, higher susceptibility to cold and flu
- Weight gain
- Depression and other mental health-related mood issues
- Problems with memory
- Higher risk for all-cause death caused by lowered attention and energy
- Type 2 diabetes
- Cardiovascular issues like high blood pressure or heart disease
According to the National Institutes of Health, between 50 and 70 million people in the US chronically suffer from either a sleep or circadian rhythm disorder, while 30% of people self-report feeling as though they get less than the recommended amount of sleep each night on average.
There are a number of different sleep disorders people can suffer from. These include:
People who have sleep apnea experience very shallow breathing or a complete stoppage in breathing several times throughout the night. This can cause snoring or other sleep disruptions.
Insomnia is having general difficulty with falling or staying asleep even when there is ample opportunity to sleep.
Hypersomnia is characterized by excessive daytime sleepiness. Sleeping periods for people with hypersomnia tend to exceed 10 hours.
REM Sleep Behavior Disorders
People with this disorder do not have the paralysis that comes with REM sleep cycle, meaning they can act out their dreams. These dreams are normally vivid, intense or violent.
Circadian Rhythm Disorders
This sleeping disorder is characterized by a lack of natural internal clock that normally makes people sleep at night and be awake during the day. Shift work can eventually cause this.
Non-24 Sleep Disorder
People with Non-24 find themselves going to bed gradually later and later and waking up later each day until they go all the way around the clock.
Periodic Limb Movement Disorder
PLMD is characterized by the repetitive cramping or jerking of the legs during sleep.
Symptoms of sleep disorders include snoring, having vivid nightmares or not feeling well-rested despite getting more than the requisite amount of sleep.
Treatment Options for Sleeping Issues
Sleeping disorders may not seem very dangerous at first, but there are many serious health consequences associated with not getting enough sleep each night.
It is important to consult with a physician or sleep specialist if you believe you are affected by a sleeping disorder.
There are a number of prescription medications available to help promote sustained sleep, but none should be taken without first talking to a doctor – preferably a sleep physician.
There are certain lifestyle changes you can make to help promote better sleeping health in your life. Some changes can include:
- Creating a sleeping schedule and adhering to it for consistency.
- Keeping tabs of the foods and beverages you consume to avoid caffeine, sugar or large amount of food right before sleep.
- Set a good mood for sleep. Invest in a good mattress and pillow and keep it as dark as possible.
- Avoid staring at your phone before trying to go to sleep.
- Exercise daily, which promotes healthier bodies in general.
- Avoid napping during the day.