Stages of sleep : Understanding the Science Behind Rest
Sleep is a time when your body and mind slow down, but your brain stays active. You become less aware of your surroundings, your muscles relax, and you react less to things around you. However, unlike being in a coma, your brain is still working and processing information while you sleep.
When you sleep, your body goes through two main phases:
Non-REM (NREM) Sleep – (The Deep Rest Zone)
Non-Rapid Eye Movement (NREM) sleep is the first three stages of sleep, where your body and brain gradually slow down and repairs itself.
Light Sleep (Stage1: N1) – You’re just drifting off. Your breathing slows, and your muscles relax. Wake up now, and you might not even realize you were asleep!
Getting Deeper (Stage2: N2) – Your body cools down, and brain activity slows, but there are still little bursts of activity. You’re sleeping, but not too deeply yet.
Deep Sleep (Stage3: N3) – This is the good stuff! Your body repairs itself, builds muscles, and boosts your immune system. It’s the hardest stage to wake up from.
REM Sleep – (The Dream Factory)
REM sleep is a sleep stage where you dream the most, your eyes move quickly, your body stays still, and your brain becomes super active. It helps with memory, learning, and emotions.
This is where dreams happen! Your body is “paralyzed” to stop you from acting them out.
Your eyes move rapidly (even though they’re closed), your heart rate speeds up, and your brain becomes super active—just like when you’re awake.
These stages repeat all night, helping you rest, heal, and feel refreshed. So, getting enough good sleep is like hitting the reset button for your body and mind! Further reading.
A full sleep cycle takes about 90 minutes, and you go through 4 to 6 cycles each night.
The Sleep Cycle
Your sleep moves in cycles, switching between deep sleep (slow-wave sleep) and dream sleep (REM sleep). This pattern, known as the sleep cycle, repeats every 70 to 110 minutes (about 90 minutes on average).
Think of it like a rollercoaster—your body shifts between calm, restful sleep and active, dream-filled sleep. Even during the day, your body follows natural energy ups and downs, like a built-in rhythm. Understanding this can help you sleep better and feel more energized!
Using data from the 2020 Behavioral Risk Factor Surveillance System, we estimated that 33.2% of U.S. adults (18 and older) sleep less than 7 hours per day. Source.
Factors Affecting Quality of Sleep
Many things can affect how well you sleep, like stress, emotions, weight, exercise, drinking, smoking, and even phone use.
- Stress can make it harder to sleep, especially for people aged 19 to 38. But doing things like hobbies, exercise, and positive thinking can help!
- Young adults often struggle with too much screen time, binge drinking, and caffeine, which can make sleep worse.
Tips for Better Sleep
To sleep better, practice good sleep habits (also called sleep hygiene). This means:
- Keeping a calm and comfortable bedroom
- Avoiding too much caffeine, alcohol, or nicotine
- Managing stress and emotions
- Staying active during the day
Making small changes can help you sleep longer and better every night!
