When you fall asleep, your brain moves back and forth between different stages of sleep. Each sleep stage is important for overall sleep quality.
The four stages of sleep that comprise a sleep cycle are: Stages N1, N2, N3 (deep sleep), and Rapid Eye Movement (REM) sleep
A complete sleep cycle lasts approximately 90 minutes. Most people experience 4-5 cycles per night.
Each sleep stage is important for overall quality sleep, but deep sleep is especially vital.
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