The short version
- Sleep hygiene means the daily habits and bedroom conditions that help you sleep well.
- It works by supporting two body systems: your internal clock and the pressure to sleep that builds while you are awake.
- A regular wake-up time, a wind-down hour, and a quiet, dark, cool bedroom are the core of it.
- Caffeine, alcohol, nicotine, large late meals and screens close to bedtime all work against sleep.
- If you have had trouble sleeping for months, good habits alone may not be enough. See a doctor.
"Sleep hygiene" sounds as though it has something to do with clean sheets. It does not. It is the term health professionals use for the habits and surroundings that help you sleep well, and it is usually the first thing they suggest when sleep goes wrong.
The NHS describes it simply: making small changes to habits and routines that help you sleep can make a real difference. This guide explains the reasoning behind those changes, which makes them much easier to stick to.
Why sleep is worth the effort
Sleep is not idle time. The US National Institute of Neurological Disorders and Stroke describes quality sleep, in the right amount and at the right times, as being as essential to survival as food and water. While you sleep, your brain and body stay remarkably active.
According to the US Centers for Disease Control and Prevention (CDC), getting enough sleep can help you:
- get sick less often;
- stay at a healthy weight;
- reduce stress and improve your mood;
- improve your heart health and metabolism;
- lower your risk of conditions such as type 2 diabetes, heart disease, high blood pressure and stroke;
- improve your attention and memory.
Good sleep has two parts. One is quantity: most adults need at least seven hours, as we explain in How much sleep do you really need?. The other is quality: sleep that is uninterrupted and refreshing.
The two systems that control sleep
Sleep hygiene makes more sense once you know what it is trying to influence. Two internal systems work together to decide when you sleep.
Your body clock. Your body runs on a rhythm of roughly 24 hours, called a circadian rhythm, which controls when you feel alert and when you feel sleepy. It is set mainly by light. Daylight tells the clock that it is daytime; darkness allows the body to prepare for sleep.
Sleep pressure. The longer you have been awake, the stronger the urge to sleep becomes. That pressure builds through the day and is released as you sleep.
You fall asleep most easily when these two line up: sleep pressure is high and your clock says it is night. Almost every piece of sleep hygiene advice is a way of keeping them in step. Irregular hours confuse the clock. Long late naps release pressure too early. Bright light in the evening tells the clock that it is still day. Caffeine masks sleep pressure without removing it.
The core habits
The advice from the NHS, the CDC and the US National Heart, Lung, and Blood Institute (NHLBI) is strikingly consistent.
Keep regular hours
Go to bed and get up at about the same time every day. The NHS explains that this helps your body know when it is time to sleep. The NHLBI suggests keeping the same schedule on weeknights and weekends, limiting the difference to no more than about an hour, because staying up late and sleeping in at weekends can disrupt your body clock.
Of the two times, the wake-up time matters more. Getting up at a fixed hour anchors the whole rhythm, even after a poor night.
Wind down before bed
Sleep does not arrive on command. The NHLBI recommends using the hour before bed as quiet time, avoiding intense exercise and bright artificial light, such as from a television or computer screen, because light may signal to the brain that it is time to be awake.
The NHS suggests relaxing before bed with something like reading, breathing exercises, calming music or a podcast, and advises trying not to use phones, tablets or computers for an hour before bed.
Make the bedroom suit sleep
All three sources describe the same room: quiet, dark and cool. The NHS suggestions include:
- earplugs if noise is a problem;
- closing the curtains fully, or wearing an eye mask;
- putting your phone on silent and placing it face down;
- keeping clocks out of view;
- adjusting the temperature or opening a window, if it is safe to do so.
Watch what you eat and drink
- Caffeine. Tea, coffee, cola and some other soft drinks contain caffeine, a stimulant. The NHLBI notes that its effects can last up to eight hours, so a cup of coffee in the late afternoon can make it hard to fall asleep at night. The CDC advises avoiding caffeine in the afternoon and evening.
- Alcohol. It may make you drowsy, but it can disrupt sleep. The CDC and the NHLBI both advise avoiding it before bed.
- Nicotine. It is a stimulant too.
- Food. Avoid heavy or large meals within a few hours of bedtime. A light snack is fine.
Use the day well
What you do during the day affects the night. The NHLBI recommends spending time outside every day when possible and being physically active. Daylight strengthens your body clock, and activity helps you sleep. Very vigorous exercise close to bedtime can keep some people awake, so earlier in the day is safer.
Be careful with naps
A short nap can boost alertness. The NHLBI advises that adults nap for no more than 20 minutes, and that if you have trouble falling asleep at night you should limit naps or take them earlier in the afternoon. If you have insomnia, the NHS advice is not to nap during the day at all.
Do not try to force it
Lying in bed trying hard to sleep tends to produce the opposite. The NHS suggests that if you are still awake after about 20 minutes, you get up and sit somewhere comfortable, do something relaxing, and return to bed when you feel sleepy.
A summary you can use tonight
| Do | Avoid |
|---|---|
| Get up at the same time every day | Long lie-ins after a bad night |
| Get daylight and some activity during the day | Caffeine in the afternoon and evening |
| Give yourself a quiet hour before bed | Screens and bright light close to bedtime |
| Keep the bedroom quiet, dark and cool | Alcohol, nicotine and large meals late on |
| Get up for a while if you cannot sleep | Lying awake watching the clock |
Our companion guide, Simple habits for better sleep, turns these into a step-by-step evening routine.
Common misunderstandings
"I can catch up at the weekend." Sleeping in for hours shifts your body clock and makes Sunday night harder. A consistent schedule works better than a cycle of shortage and recovery.
"A drink helps me sleep." It may help you fall asleep, but alcohol can have a disruptive effect on sleep.
"I should stay in bed until I drop off." Lying awake trying to force sleep rarely works. The NHS advice is to get up after about 20 minutes, do something calm and return when you feel sleepy.
"If I do everything right, I will sleep perfectly." Everyone has the occasional bad night. One or two do no harm, and worrying about them does more damage than the lost sleep.
The limits of sleep hygiene
Sleep hygiene is good general practice, in the way that brushing your teeth is. It prevents a great many problems. It is not, by itself, a cure for every sleep difficulty.
The NHS notes that insomnia usually gets better by changing your sleeping habits, but it also advises seeing a doctor if changing your habits has not helped, if you have had trouble sleeping for months, or if your insomnia is affecting your daily life in a way that makes it hard to cope. A doctor will look for the cause and may refer you for cognitive behavioural therapy, a structured treatment that helps to change the thoughts and behaviours that keep you from sleeping.
Some sleep problems have a physical cause. The CDC lists insomnia, restless legs syndrome, narcolepsy and sleep apnoea among the common sleep disorders. No amount of good habit will fix these without proper assessment.
Where to start
You do not need to adopt every habit at once. Begin with a fixed wake-up time and hold it for two weeks. It is the change with the largest effect on everything else, and it costs nothing.
References
- How to fall asleep faster and sleep better. NHS, Every Mind Matters.
- Healthy Sleep Habits. National Heart, Lung, and Blood Institute (NIH).
- About Sleep. Centers for Disease Control and Prevention.
- Brain Basics: Understanding Sleep. National Institute of Neurological Disorders and Stroke (NIH).
- Insomnia. NHS.
Written by
The Diurna editorial team researches and writes each guide, working from public-health guidance and peer-reviewed research.
