Today is World Sleep Day. The aim of this is to encourage people to prioritise their sleep to improve overall health and wellbeing and to draw society’s attention to the burden of sleep problems. This is a chance to ask yourself “Am I sleeping well enough to allow me to function properly during the day?” This is a question of sleep quality and quantity. But how much sleep is enough? Naturalmat’s resident sleep expert Christabel Majendie has answered that question to ensure you’re getting you’re getting the right number of hours.

Whenever I ask someone “how much sleep do you think you need?” the most common answer is, “eight hours.” But no one is the same when it comes to sleep so it’s important to work out your own individual need.


1. Sleep duration not only varies between individuals, but it changes with age.

So, while a new-born may need between 14-17 hours a day, by the time a child is in school, their sleep requirement has dropped to 9 to 11 hours. This drops by about one hour in adolescences then stabilises in adulthood.


2. The average sleep duration for an adult is between 7 and 9 hours.

But even this can be misleading as this is the average range and doesn’t include the natural extremes. While the majority fall within this range, there are naturally short sleepers and others are naturally long sleepers. Trying to sleep for less than your own individual sleep requirement will lead to sleep deprivation. Equally, trying to sleep for more than your natural sleep duration will lead to problems such as not being able to drop off to sleep or waking in the night unable to get back to sleep.  It’s the same with sleep timing – your preference for when you get up and when you go to bed is individual to you; some people are naturally owls; some are larks and other people fall in between. This is referred to as your circadian rhythm. Genetics is likely to play a part in this but sleeping patterns are also heavily influenced by light.


3. What is the best sleep duration?

There has been a wealth of research looking at short and long sleepers and associated health problems. These studies have found both short sleep (less than 6 hours) and long sleep (more than 10 hours) are associated with a number of long-term health conditions such as cardiovascular disease, obesity, certain cancers, mental health problems and reduced life expectancy. While these findings are alarming, it’s important to understand that these studies are saying there is a link between sleep duration and health. The studies are not saying that short or long sleep duration causes these health problems; indeed, it could be the other way around i.e. that short or long sleep is due to an underlying health condition. Or it could be that other factors are linking sleep duration and health conditions together so there is no direct link.


Having said all that, there is now a fairly large, reliable body of evidence to say that sleep deprivation leads to health problems. So, we should all aim to not sleep deprive ourselves. Generally, less than six hours is too little, apart from a few rare individuals. The clearest indication that you are sleep deprived is that you feel excessively sleepy in the day (although this could also be due to a sleep disorder), and/ or actually falling asleep during the day. Sleepiness is different to tiredness; the latter doesn’t necessarily lead to sleep.


4. What about napping?

There is mixed advice about napping; some say don’t others say do. If you are sleep deprived, napping is essential. But a better approach would be to get more sleep at night. If you get enough sleep at night, but still find a short nap beneficial in the day, then that’s a good thing so keep doing this! 10-15 minute is best before 3pm. However, if you are struggling to sleep at night, the advice is to not nap during the day, as this may affect your nocturnal sleep, particularly if you nap for a long time and too late in the day. Remember napping includes dozing off on the sofa in front of the TV in the evening!


5. How do you find your own perfect sleep duration?

The best way to find your own optimal sleep duration is on holiday. For many people, the first few days of holiday may involve clearing a “sleep debt” caused by travel- induced sleep deprivation or getting over jetlag, so discount these first few nights. After this your sleep duration should stabilise. Note down when you start to feel naturally sleepy at night and go to bed at this time (be aware this will be influenced by alcohol, stimulants and recreational drugs so it’s best to avoid these). Sleep without an alarm clock and see when you naturally wake in the morning. Keep a sleep diary that records these times over a period of a week, and then calculate your average sleep duration over a period of 7 to 14 days (this is different to your time in bed). This is a pretty good estimate of your optimal sleep duration. From this diary you will also see a pattern emerge around your preferred time of going to bed and waking up. This is a good indication of your natural circadian rhythm or body clock.


6. Follow your signs

When you are finding the sleep right for you, it’s important to look out for your signs of sleepiness (increased yawning, a feeling that you will nod off, droopy eyes etc.) and to go to bed at this time. Don’t follow someone else’s pattern or society’s time. You will also need to dim the lights in the evening (or sit outside in the dark) and to spend a good amount of time outside in the day as this will strengthen your circadian rhythm. You don’t necessarily have to have eight hours of sleep – you may need more or less than this; work out what is best for you. You wouldn’t try to fit into a pair of shoes that are not your size. You need to have the same approach to sleep by finding your own natural sleep duration and timing.