Submitted by Metagenics Marketing Team
For optimal health, most adults should aim for about seven to nine hours of sleep a night. Maybe you’re in that range — but are you sleeping soundly enough?1
When your head hits the pillow, it takes a while to enter the deep sleep stage, and if you have poor sleep quality, you may not be getting the deep sleep you need to feel rested in the morning. If you’re curious about why deep sleep is important to your health and well-being, you might want to better understand your sleep patterns and learn how to track these deep sleep cycles.
Our sleep cycles: what is NREM and REM sleep?
Our brain goes through two types of sleep in a typical night: non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep.2
We generally start our sleep cycle by going through the stages of NREM sleep before moving into a short period of REM sleep. NREM sleep consists of three distinct stages, known as N1, N2, and N3. Each stage is associated with different types of brain activity, with N3 being where we experience deep sleep. During REM sleep, our eyes move rapidly from side to side with the eyelids closed.2 Dreams usually occur during REM sleep as well. The cycle then repeats itself until we are fully rested. We go through these stages about 4 to 6 times each night, averaging 90 minutes each cycle.1
But to understand when we sleep that important deep sleep and how to monitor it, we need to delve into the three stages of sleep that occur during NREM.
What are the stages of sleep?
Let’s break down what happens in the brain and body during the three stages of sleep:
- Stage 1 is the initial phase of sleep, lasting 5 to 10 minutes. It involves light sleep with slower heart rate, breathing and eye movements. Muscles are relaxed and occasional twitching may occur. Brain waves are also slow. This stage is not particularly deep, so you are more prone to awakening.2
- Stage 2 is the period of light sleep before deep sleep. Your heart rate and breathing increase even more slowly. Your body temperature drops and muscles continue to relax.1.2 Eye movements stop. Stage 2 involves only brief periods of electrical activity in the brain. You spend more time here than in any other NREM sleep stage. Stage 2 sleep prepares you for deep sleep and accounts for about 50% of the sleep cycle.3
- Stage 3 it is deep sleep, also known as delta sleep, slow wave sleep, or N3 sleep. In this stage, your heart rate and breathing slow to the lowest levels that occur throughout the night. Your muscles also continue to relax and your brain waves grow even more slowly.1 Deep sleep takes place longer early in the night and becomes shorter as you progress through the sleep cycle. It lasts 45 to 90 minutes initially and accounts for about 13-24% of our total sleep.3
What are the benefits of deep sleep?
Deep sleep helps support memory, learning ability and glucose metabolism in the brain. Additionally, the pituitary gland—which is associated with growth and development among other functions—is very active during this part of the sleep cycle. Adequate deep sleep also offers psychological benefits, improving mood and energy.4 In contrast, chronic sleep deprivation and poor stage 3 sleep are associated with negative effects on the brain and heart.
Other benefits of deep sleep include:3
- Tissue regeneration
- Bone and muscle development
- Immune system support
- Restore energy
- Growth of new cells
- Increased blood supply
How can you monitor your deep sleep?
When tracking your deep sleep, you can consider the following options:
- Phone Apps: While it’s a good idea to keep your phone out of the bedroom at night, if you decide to sleep with it nearby, you can use apps that track your deep sleep using sonar waves. Place your phone on the mattress and check in the morning to see how much you moved and how deeply you slept.5
- Mobile Devices: Do you wear a Fitbit or an Apple Watch? If so, consider wearing your device while you sleep. It can track your movement and provide information on overall sleep efficiency and quality. However, keep in mind that these wearables were not specifically designed for sleep monitoring, so their results may not be completely accurate.5
- Smart beds and sleep sensors: For more accurate deep sleep monitoring, you can place sensors above or below your mattress. They monitor movement, heart rate and breathing, providing data on REM and non-REM sleep stages. Popular options include Sleep Number 360® Smart bed, iFit Sleep HR and Eight Sleep Tracker.5
If you really have problems with your sleep quality, see a doctor. A specialist can perform a polysomnography (PSG) test to gather more information about your sleep patterns and your overall sleep quality. Making sleep a priority and ensuring restorative deep sleep is an essential part of caring for your overall well-being. It’s an investment in yourself that can have a profound impact on your health and happiness.
Metagenics offers a variety of products to support restful sleep:
- Formulas for occasional insomnia: MetaRelax, Tran-Q™ Sleep
- Formulas to help you fall and stay asleep: MetaSleep™
bibliographical references
- National Institutes of Health Staff. Brain Basics: Understanding Sleep. National Institute of Neurological Disorders and Stroke. https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Understanding-Sleep. Accessed 29 January 2019.
- Felson S. What is REM and non-REM sleep? WebMD. https://www.webmd.com/sleep-disorders/guide/sleep-101. Accessed 29 January 2019.
- Murrell D. What is deep sleep and why is it important? Healthline. https://www.healthline.com/health/deep-sleep#benefits. Accessed January 30, 2019.
- Cline J. The Mysterious Benefits of Deep Sleep. Psychology Today. https://www.psychologytoday.com/us/blog/sleepless-in-america/201010/the-mysterious-benefits-deep-sleep. Accessed 29 January 2019.
- CNET Staff. The 3 best ways to track your sleep. CNET. https://www.cnet.com/how-to/how-to-track-your-sleep-schedule. Accessed January 30, 2019.
This content is not intended as a substitute for professional medical advice, diagnosis or treatment. Individuals should always consult their healthcare professional for advice on medical issues. For more information on sleep and stress management hi, visit it Metagenics Blog.
