It's extremely common for people to describe themselves as light or deep sleepers; light usually meaning you wake up easily throughout the night, whilst deep sleepers could sleep through the loudest noises imaginable.

In truth, we all experience stages of light, deep and Rem sleep throughout the night and each stage of sleep is as important as the next. Deep sleep is by far the most important as this is when our bodies perform many of it’s own vital functions to recover from the previous day and to prepare for the next. People who state they sleep deeply tend to report feeling more well rested. But how much deep sleep do we need?


What is Deep Sleep?

Deep sleep is known as the third and fourth stage of our sleep cycle, when our brain waves slow right down, our muscles relax and our heart rate and breathing slow down.

Deep sleep is the main part of your sleeping cycle in which the body will repair itself, release growth hormones and strengthen the immune system. The body is busy during this time but the brain becomes very inactive.This isn’t the part of our sleep cycle that dreams occur (this happens during the REM stage) and we’re less responsive to outside stimuli which is why it’s hard to wake up from a deep sleep state. If you are woken up during a deep sleep, you’ll find your brain needs a couple of minutes to catch up.


How much deep sleep do we need?

We know why we need it, but how many hours per night of deep sleep is enough?

Even though a lot of important repairs within the body happen in deep sleep, we don’t spend the largest portion of time in this stage. We typically spend around 15-25% of our night in this state. Light sleep takes up the majority at around 50-60% and roughly 20% in the REM cycle.The average hours of deep sleep we need does indeed vary by age.

The average adult over 18 needs 7-9 hours sleep per night, with around 2 hours spent in deep sleep according to the New Health Advisor, but this does differ for younger people.Babies and young children spend more hours in deep sleep in order to have time to release the growth hormones needed for a strong development.

New borns will spend around 3-4 hours per night in a deep sleep state, decreasing over time as they get older.

The 15-25% proportion remains the same for children however there is a big shift in proportion from deep sleep to light sleep during adolescence.

Studies show the time spent in deep sleep decreases at a rate of around 2% per decade between the ages 20 and 60.Some people need more deep sleep than others to wake up feeling refreshed so ultimately there is no such thing as too much sleep! If feel like you want a lie in then do, your body is telling you what it needs.

The older generation may experience less deep sleep due to aches and pains and not being able to get comfy. Unfortunately their body could need more but these factors can limit how much deep sleep they’re able to get. 


What happens when we don’t get enough deep sleep?

As already mentioned, the deep sleep stage is all about looking after the body.

Lack of deep sleep is most impactful in the early years when growth hormones are needed the most, but lack of sleep can effect adults to.During deep sleep the body replaces cells, heals wounds and builds muscle tissues, as we as strengthening the immune system. If you don’t get enough sleep, you’ll likely feel run down & pick up illnesses more often.Struggling to wake up in the mornings, feeling groggy for prolonged periods of time can also suggest. You’re not getting enough deep sleep.

You may also be more cranky during the day or find yourself feeling more emotional due to having no energy.

How to get more deep sleep…

If you feel like you’re not getting enough deep sleep, there are several things you can try. A good place to start is to find out more about your sleeping pattern. The best way to do this is to download an app onto your smart watch, where possible, like a Fitbit or your Apple Watch. Tracking your sleep will help you see how many hours of each stage of the sleeping cycle you’re getting and how many times you wake up throughout the night. Some apps may even score your nights sleep to help you track your sleeping pattern.

Stress is a massive cause of unsettled sleep, so do everything you can do relax before bed. This can include -

  1. Picking up a book
  2. Take a warm bath
  3. Try some mediation to calm your mind
  4. Avoid caffeine in the evening
  5. Exercise Regularly
  6. Establish a sleep routine and set bedtime
  7. Make efforts to not sit in front of a screen at least 1 hour before bed
If you tend to sit infront of your phone screen before bed, be sure to use a dimmer screen setting or a blue light filter to stop the blue light glare where possible.