Why Deep Sleep Helps Your Brain

Anyone who’s spent a long night tossing and turning understands the value of a good night’s sleep. It’s not just the number of hours you spend in that bed, it’s the quality of sleep you get while you’re there that matters. 

Deep sleep slows down your brainwaves, which consolidates memories and restores the body and brain, according to the American Sleep Association (ASA). If you wake up feeling unrefreshed, you may not have experienced this critical sleep stage. 

When you don’t get enough quality sleep, it can affect all areas of your life. The most obvious impact is that tired and listless feeling that sticks with you throughout the day. Less noticeable is the potential damage being done to your brain health over the long term. 

Adults should get seven hours of sleep per night in a dark, quiet room with no visual stimulation. When you’re stressed, over-caffeinated or your body temperature is unregulated — meaning you feel too hot or too cold — it can be difficult to fall into deep sleep. But there are things you can do to boost your chances of a good night’s rest. 

Our Brains During Sleep 

During sleep, our minds and bodies are in relaxation and restoration mode while our consciousness and muscle activity decrease. The brain quietly does its job, helping the body get ready for another day of quality life. For example, our brains control the circadian rhythm, which is responsible for producing the melatonin that helps us sleep. 

There are four sleep stages, which repeat four to five times a night, as your brain cycles through two main states: NREM (non-rapid eye movement) and REM (rapid eye movement) sleep. 

-        NREM sleep

• Stage 1: Transition between being awake and asleep (lasts about 5-10 minutes)

• Stage 2: Body temperature drops and heartbeat slows (lasts about 20 minutes)

• Stage 3: Deep sleep begins, muscles relax entirely while blood pressure and breathing rate drop

-        REM sleep

• Stage 4: Brain activity increases as dreams occur 

Why Deep Sleep Matters 

Deep sleep is critical for the brain restoration that allows us to wake up feeling refreshed and ready to conquer the day. Healthy sleep is vital for “brain plasticity,” or how we process and memorize information. Not getting enough sleep can inhibit our ability to remember and focus. 

One study even found that sleep or sleep deprivation can predict the onset of Alzheimer’s disease and dementia. Another study suggests that sleep deprivation could cause the brain to shrink. 

Aside from brain health, sleep deprivation can contribute to other health risks, including: 

• Seizures

• High blood pressure

• Depression

• Increased risk of illness and infection

• Inability to lose weight

• Memory loss 

10 Tips for Better, Deeper Sleep 

There are ways to maximize your deep sleep experience each night and keep your brain feeling sharp and focused during the day. Among them: 

• Sleep in a dark and quiet room.

• Shut off electronic devices and avoid looking at bright screens two to three hours before bedtime.

• Give yourself enough time to fall asleep.

• Avoid caffeine four to six hours before bedtime.

• Consider moderate to vigorous exercise for at least 30 minutes per day.

• Listen to white noise.

• Block out light with an eye mask and block noise with earplugs.

• Track your sleep with an app or smartwatch.

• Take a melatonin supplement one to three hours before bedtime.

• Establish a comfortable bedroom temperature, ideally between 60 and 67 degrees. 

If you’re experiencing a sleep disorder like narcolepsy, restless leg syndrome, sleep apnea, insomnia or parasomnias, a doctor can suggest other sleep remedies and help you identify underlying mental or physical health problems.