What is REM Sleep? How Does it Work, Importance, and Purpose


There’s a lot going on in your body when you sleep. You are alternating between REM and non-REM sleep when you get your ZZZs.

What is REM sleep?

REM stands for Rapid Eye Movement. Your eyes will shift and dart rapidly under your eyelids during this process of your sleep. The brain activity increases during REM sleep, the heartbeat is quicker, and you have dreams. REM sleep first takes place after about 90 minutes of sleep. The first cycle usually lasts about 10 minutes, and each cycle time increases until you wake up to as long as one hour in the final phase.

Next comes non-REM sleep, in non-REM sleep, your eyes do not move rapidly like REM sleep. Followed by a shorter REM sleep period, and then the cycle begins again. Generally dreams occur during REM sleep.

What Happens During Non-REM Sleep?


There are three non-REM sleep periods. Between 5 to 15 minutes, each stage can last. Before you get to REM sleep, you go through all three stages.

Stage 1: Your eyes are closed, but waking up is easy. It can last 5 to 10 minutes in this process.

Stage 2: You are in light sleep. Your heart rate is slowing and the temperature drops in your body. The body is ready for deep sleep.

Stages 3: This is the level of the deep sleep. During this time, it’s harder to rouse you, and if someone wakes you up, for a few minutes you’d feel disoriented.

The body replaces and regenerates tissues, develops bone and muscle, and strengthens the immune system during the deep stages of Non-REM sleep.

You sleep more easily as you get older and you get less deep sleep. Aging is also correlated with reduced sleep time, while studies show that you still need as much sleep as you were younger.

Why is REM sleep good? Why is REM sleep important?

REM sleep is important for your sleep cycle as it activates the areas of your brain that are necessary for learning and memory formation or maintaining. Research depriving rats of REM sleep significantly shortened their life span from two to three years to five weeks, according to the National Institute of Neurological Disorders and Stroke. Rats deprived of all sleep cycles lived up to three weeks. The importance of REM sleep is attributed to the fact that your brain performs essential neural connections during this sleep phase that are crucial to mental and physical health and well-being.

What is the purpose of REM sleep?

Among the various theories about the role of REM sleep is that it helps to form new memories, activates the central nervous system, and restores the normal balance of brain chemistry.

How much REM sleep should you get

Although there is no official consensus as to how much REM sleep you should get. Experts believe that dreaming will help you process your thoughts and solidify your memories.

REM takes up about 20 to 25 percent for most people, and this tends to be safe during normal periods of sleep. Sleep analysis, however, poses some interesting issues. A recent study indicated that depression may be associated with higher levels of REM sleep. But don’t suddenly change your sleep habits— it’s not clear what the cause is and what the result is.

What is REM Sleep Behavior Disorder?

REM Sleep Behavior Disorder is a sleep disorder, according to the Mayo Clinic, that causes you to perform vivid dreams through erratic and violent movements of the arms and legs. This condition can happen suddenly and multiple times a night affect your sleep.

The body usually stays motionless during REM sleep, but REM Sleep Behavior Disorder signs include:

  • Movements such as flailing, kicking, or punching in response to especially vivid or frightening dreams.
  • Noises such as yelling, talking, or crying while you are sleeping.
  • Ability to vividly remember the dream you were experiencing if you are woken up.

REM Sleep Behavior Disorder may be triggered by underlying medical conditions or illness, but may have other causes such as medications, sleeping habits, or neural issues. When you have repeated physical REM sleep disturbances, a sleep study done by a qualified sleep specialist will help you determine if there is an underlying sleep disorder and allow you to take advantage of your significant REM sleep cycle once again.

How Is REM Sleep Behavior Disorder Treated?

Here are a few ways you can treat your REM Sleep Behavior Disorder:

  1. Move objects away from your bedside.
  2. Move your bed away from the window.
  3. Maintain a standard bedtime.
  4. Avoid certain medications and alcohol.
  5. Treat any other sleep disorders.

Does Melatonin Help REM sleep?

Melatonin is not a sedative. Actually, it helps to facilitate sleep by helping to control the body’s biological clock and sleep-wake cycles. Melatonin can also improve sleep quality and reduce sleepiness and exhaustion during the day. Studies also show that REM sleep can be improved

What drugs increase REM sleep?

In summary, drug effects on REM sleep include reactions to drugs that decrease REM sleep (ethanol, TCAs, trazodone, SSRIs, MAOIs, lithium, amphetamines, methylphenidate, and clonidine); reactions to drugs that increase REM sleep (nefazadone and reserpine); and reactions to the elimination of REM-suppressing drugs.

Is REM sleep good or bad?

Are you tired? Exhausted? Do you sleep normal hours but wake up feeling like you’ve never slept? You might get too much REM sleep, and your diet might drive you there. REM sleep is the stage where normal dreaming happens and the heart rate and breathing are quicker. REM sleep is known to be less restorative than a deeper sleep period–non-REM.

According to the results of a study conducted by researchers at the Perelman School of Medicine at the University of Pennsylvania, “An individual’s body composition and caloric intake can influence time spent in specific sleep stages.”

The study found evidence suggesting that adults who were overweight spent more time in REM sleep than adults with normal weight. Researchers also found that less of the restorative sleep stage was predicted by a rise in protein: Stage 2. This is the stage preceding deep sleep and slowing the heart rate.

The researchers suggested that more analysis on the effects of a diet on sleep was needed. Nonetheless, they reiterated the results of a 2015 study suggesting that “…eating less late at night may help curb the concentration and alertness deficits that accompany sleep deprivation.” Although dreaming in REM sleep can be a wonderful thing, too much of a good thing can be poor. We wish you sweet dreams–not too many!


Scientists agree that sleep is necessary for health, and while stages 1 to 3 and REM sleep are all important, deep sleep is the most essential to rest and stay healthy.

The average healthy adult gets about 1 to 2 hours of deep sleep for 8 hours of sleep at night. There are different ways to determine if you are, from using sleep trackers.

When you wake up exhausted on a regular basis, talking to a health care provider is a good idea.