To understand why sleep is important, think of your body like a factory that performs a number of vital functions. As you drift off to sleep, your body begins its night-shift work:
- Healing damaged cells
- Boosting your immune system
- Recovering from the day’s activities
- Recharging your heart and cardiovascular system for the next day
We all know the value of sleeping well, and we’ve all experienced the feeling of being refreshed after a good night’s sleep – and the feeling of fatigue after a poor night’s sleep. But even though we know this, in our busy society, many of us are not getting the quality sleep needed to truly receive the health benefits of sleep.
Understanding the sleep cycle
Understanding what happens during sleep also means understanding the sleep cycle, which consists of two recurring phases: REM (rapid eye movement) and NREM (non-REM or non-rapid eye movement). Both phases are important for different functions in our bodies.
NREM sleep typically occupies 75–80% of total sleep each night. Many of the health benefits of sleep take place during NREM sleep – tissue growth and repair occurs, energy is restored and hormones that are essential for growth and development are released.
REM sleep typically occupies 20–25% of total sleep each night. REM sleep, when dreaming occurs, is essential to our minds for processing and consolidating emotions, memories and stress. It is also thought to be vital for learning, stimulating the brain regions used in learning and developing new skills.
If the REM and NREM cycles are interrupted multiple times throughout the night — either due to snoring, difficulties breathing or waking up frequently throughout the night — then we miss out on vital body processes, which can affect our health and well-being the next day and long term.
What happens if you don’t get enough sleep?
If your body doesn’t get a chance to properly recharge – by cycling through REM and NREM – you’re already starting the next day at a disadvantage. You might find yourself:
- Feeling drowsy, irritable or sometimes depressed
- Struggling to take in new information at work, remembering things or making decisions
- Craving more unhealthy foods, which could cause weight gain1
If this happens night after night, it places a tremendous strain on your nervous system, body and overall health. So if you’re not sleeping well or aren’t feeling rested when you wake up in the morning, it’s important to talk to your doctor and ask if a sleep study is right for you.