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How much sleep do I need?
In order to function optimally, official guidelines recommend 7 to 9 hours sleep per night for most adults, whilst children need much more and older adults need slightly less. However, as well as age, other factors such as energy expenditure and recent illnesses can also cause sleep requirements to vary.
What to consider when assessing how much sleep you need
Knowing the general recommendations for sleep is an important first step, but here I take you through the other factors to consider so you help tailor your own unique sleep routine and start maximising those sleep benefits, including thinking more clearly, being able to deal with challenges, reduced stress levels, not to mention even helping with staying at a healthy weight and getting ill less often.
Professor Margareta James adds: 'Sleep is restorative, whereas sleep deprivation lowers your resistance to stress and harms your brain. Lack of sleep interferes with memory and learning. So, getting the recommended amount of sleep as well as maintaining a regular schedule of sleep and wake times is important, especially during stressful times.'
1. Age
Babies need the most sleep of all, with newborns often sleeping up to 75% of the time as they go through dramatic healthy developmental changes contributing to cognitive and psychosocial development.(1) As we age, this requirement goes down and changes (although there may be a requirement for a small increase again during the teenage years due to the demands that going through puberty can have) and so, by the time we reach adulthood, the general recommendation is to aim for between 7 and 9 hours of sleep per night.
Older adults may be on the shorter end of this window due to sleep requirements being a little less by the time we reach our later years. This can be down to a variety of reasons such as reduced activity, decreased energy expenditure and other bodily processes gradually starting to slow and requiring less energy to maintain.
How much sleep do I need by age?
Whilst our advice is mainly aimed at adults, it can be interesting to have some understanding of how our sleep needs change with age, plus, there is some variation in the requirement between adults of different ages. The general sleep recommendations categorised by age are as follows:
| Age | Sleep requirements |
| Babies and young children under 6 | 10 - 17 hours depending on age |
| School age: 6 - 12 years | 9 - 12 hours |
| Teenagers: 13 – 18 years | 8 – 10 hours |
| Adults: 19 – 64 years | 7 – 9 hours |
| Older adults: 65 + | 7 – 8 hours (2) |
Of course, age is only one factor and you should always consider everything else that is going on in your life, to help determine exactly how much sleep you require.
2. How you feel
As a nutritionist I feel strongly about listening to your body, and ultimately this for me is the most important consideration of all when it comes to determining how much sleep you need. The general guidelines are a good start, but ultimately it is individual to you. There are clues that you are not getting enough sleep, so here are a few questions I'd like you to ask yourself:
- Do you feel rested and energised or still tired after a night's sleep?
- Do you experience morning or afternoon slumps in energy?
- Do you rely heavily on an alarm to wake in the morning or can you wake up without one?
- Do you find it difficult to stick to regular wake-up times, i.e. you take the opportunity to lie in when you can?
- Do you rely on caffeine and refined sugar to help give you energy throughout the day?
- Do you find yourself craving junk food?
These are just some of the tell-tale signs that indicate you might not be getting enough sleep. So, it's always a good idea to consider your sleep habits first if you tick a lot of these boxes, but please note there can be a number of other factors at play too.
Also, a poor diet can also bring about some of these symptoms, particularly as a result of poor blood sugar regulation. See, peaks and then troughs in blood sugar levels a few hours after eating, or even in the early hours of morning, can bring about dips in energy or affect sleep routines. Wobbly blood sugar issues and poor sleep often go hand in hand.
A few dietary tips from me to help counter some of these effects can include:
- Balancing each meal with a good quality protein, healthy fats as well as a source of complex carbohydrates.
- Cooking fresh meals rather than opting for more processed ingredients that can make it harder to achieve a well-balanced meal.
- Incorporating blood sugar balancing spices into your daily diet, such as cinnamon, which can help to improve insulin sensitivity. (3)
- Limiting sources of caffeine. Whilst caffeine can technically help to bring about a lift in energy initially, this will risk causing huge crashes a short while later. Limit caffeine later in the day, even as early as 2pm to avoid disturbing your sleep at night too.
Please also note that symptoms such as those associated with:
- Anxiety
- Depression
- Lack of memory or concentration
- Low immunity
- Chronic pain or
- Pre-diabetes (including cravings)
may also be some less obvious consequences of poor sleep.
Professor Margaret James adds: 'After a good sleep, you should feel energetic throughout the day, including your cognitive performance (attention, memory, concentration) being where you want it to be. Because lack of sleep takes its toll on our cognitive and mental health and over time, problems with mood, memory and other issues can become chronic and a way of life, putting people at greater risk of depression, because sleep and mood affect each other.'
Of course, you should always check with your doctor if you are experiencing these symptoms and are struggling to get them under control. In some cases, better sleep can have a number of positive, whole-body effects, including maintaining your weight, glowing clear skin, good mood influenced by healthy hormonal functioning.
3. Your energy expenditure
The sleep you require at night depends on the energy you have expended during the day to some degree. Remember, you expend energy through physical movement, using your brain power and even by eating! So, how much energy you exert can also determine how much sleep you need at night, and this could vary from day to day or around different phases in your life.
Remember, sleep is the most restorative practice you can partake in. Whilst you sleep, your brain is able to repair and grow cells, tissue and nerves that regenerate and boost your hormone and immune system. Remember, alongside stress reduction and good nutrition, restorative sleep is vital for your optimal physical, mental, and emotional health. (4) If you are expending too much energy each day and not catching up on the necessary sleep at night, you can risk being faced with 'burnout' in the long-term.
4. You've been unwell
If you've been unwell, for example fighting off a cold and flu infection, you may need to sleep more than usual and this would most certainly be recommended. Sleep and the immune system rely very much on each other and there is evidence that good sleep can help in fighting off infections quicker. The immune system needs sufficient sleep to work optimally. See, in the event of an active infection, your immune system has to work harder than ever to help you overcome it. Too little sleep and the infection could get the better of you and you might find your symptoms are prolonged. Alternatively, you risk falling ill quite quickly again with yet another infection, which is known as a secondary infection.
If you have a well-functioning immune system, it can help you to stay asleep as a result of releasing helpful sleep-promoting cytokines (proteins that help the immune system by targeting infection) during the night. (5) They are produced and released during sleeping, so more sleep during illnesses can help with recovering faster. Just make sure daytime naps don't take away from your overnight sleep. My advice is to go to bed that little bit earlier if you've been unwell and listen to your body during the day too, in case the need for an emergency nap comes calling!
Do you need help sleeping?
Whilst some people understand how much sleep they should be getting in order to function at their best, in some cases, falling asleep when required is easier said than done.
Havening (6) - a technique that generates delta brain waves can help with falling asleep or falling back to sleep if you wake up in the middle of the night, helping you to enjoy a deep, restorative sleep.
If you feel you still need some help following asleep, click this link for a whole blog on our top tips for overcoming problems falling asleep. For a quick fix, Dormeasan can also be helpful. Take Dormeasan containing fresh extracts of Valerian and Hops to help you wind down in the last half hour before bed.
Can you sleep too much?
A less common issue admittedly, but you might wonder if it's possible to sleep too much and the answer is yes. Whilst too little sleep can be associated with issues such as mental health issues, poor memory or a compromised immune system, routinely having too much sleep called hypersomnia (more than 9 hours) may put us at greater risk of poor health outcomes. (7)
Then, always in with your doctor if your sleepiness symptoms last longer than six weeks. You can prepare for your appointment by keeping a sleep diary.
Reviewed and approved by Professor Margareta James.
