Deep sleep: how much do you need?
The quality of your sleep is essential to you feeling your best in the morning and being able to tackle the tasks ahead, so how much deep sleep do you need to feel functional and alert? Let’s explore.
What is deep sleep?
When you go to sleep at night, you cycle through 5 stages of sleep. Deep sleep consists of stages 3 and 4 of non-rapid eye movement sleep (non-REM). As you enter stage 3, the brainwaves which are also called delta waves are infused with small waves which move quickly through the brain.
With the onset of stage 4, which is the final of the stages of deep sleep, eye movements cease, and the muscles completely stop moving. In stage 4, the body regenerates itself, prompting growth and development as it heals the cells, leading to tissue growth and the release of hormones.
Some people confuse the REM and the deep stages of sleep, but the two are very different. With REM, the body is more alert, with an increase in the heart rate and breathing while in deep sleep, the body goes into a more still phase with bodily functions slowing down to allow the body to repair itself.
What are the benefits of deep sleep?
Getting valuable sleep may lead to an extra bounce in your step the next day, and the reasons are multiple.
1. Memory consolidation
The quality of your sleep plays a role in the creation and maintenance of your memories. Studies show that deep sleep enhances your brain’s ability to store information. This is how memories are stored. It is linked to being able to remember data and is useful in learning and retaining information.
2. Tissue repair
Several hormones are released during the deep stage, which is necessary for the growth and repair of the body’s cells. The pineal gland emits melatonin which regulates the sleep cycle while the pituitary gland releases growth hormone which helps the tissues to grow and regenerate themselves.
3. Strengthen the immune system
Cytokines, a protein that is released during the deep stage, helps the body to fight off infections and viral attacks. Not getting enough deep sleep will lower your body’s ability to fight off an infection. The body also produces T-cells during the deep stage of sleep, which are an active line of defence against viruses. T-cells bind onto infected cells, combating viruses.
4. Energy restoration
The deep stage of sleep is essential to building up your energy reserves as it enables the brain to replenish energy by storing glucose and releasing it when you wake up. The hormone cortisol, which is an energy booster increases as you sleep so that you can feel alert in the morning.
How many hours of deep sleep do you need?
Research conducted on sleep and how much you need has shown that an adult over the age of 18 requires 7-9 hours of sleep every night. Of that amount, between 1.5 and 2 hours should be spent in deep sleep.
The brain regulates the sleep patterns, and when sleep is disrupted, this can lead to a shortage of deep sleep. It isn’t possible to have too much deep sleep because the brain naturally regulates the stages of sleep to ensure you get the right amount. It is possible to monitor how much sleep you are getting in each stage of sleep with a sleep monitor.