How to sleep better: what the evidence actually supports

Few things affect how a day feels as much as the night before it. After a poor night, patience runs thin, focus scatters, and even small tasks feel heavy. After a good one, the same day can feel manageable.

Sleep advice is everywhere, and much of it is contradictory, expensive, or both. Supplements, gadgets, elaborate bedtime rituals. This guide sets that aside and focuses on what reputable health bodies and research reviews actually support, where the evidence is strong, where it is thinner than you might expect, and when poor sleep is a reason to see a doctor rather than try harder on your own.

How much sleep do you need?

The US Centers for Disease Control and Prevention (CDC) recommends at least seven hours a night for adults aged 18 to 60, seven to nine hours for those aged 61 to 64, and seven to eight hours from 65 onward. The NHS says most adults need between seven and nine hours.

These are averages, and individuals vary. A more useful personal test is how you feel during the day. The NHS notes that if you are constantly tired during the day, you are probably not getting enough sleep.

Sleep is not a luxury you earn after the important things are done. It is one of the important things, and it affects mood, focus and safety the next day.

A note on “sleep hygiene”

Most sleep advice falls under the heading of sleep hygiene: habits and surroundings that support sleep. It is worth knowing something that is rarely said out loud.

A 2015 review in Sleep Medicine Reviews by Irish and colleagues pointed out a puzzle. Individual sleep hygiene recommendations, such as regular exercise, avoiding caffeine late in the day, and keeping a regular schedule, are each linked to better sleep in research. Yet sleep hygiene education on its own has generally been ineffective as a treatment for insomnia. The authors also noted that the direct effects of individual recommendations remain largely untested in the general population.

In plain terms: these habits are sensible and supported by evidence on their own, but a list of ten rules is unlikely to fix serious sleep problems by itself. Pick the few that fit your life and do them consistently, and if you have chronic insomnia, look at the proper treatment described below.

The habits with the best support

Keep a regular wake-up time

Both the CDC and the NHS put a consistent schedule near the top of their advice. The NHS specifically recommends getting up at the same time every day, and avoiding sleeping in after a bad night.

This can feel unfair. After a rough night, a lie-in seems like the obvious fix. But a regular wake-up time anchors your body clock. Your internal clock runs on roughly 24-hour cycles, and according to the US National Institute of General Medical Sciences, light and dark have the biggest influence on those rhythms. A steady wake time, ideally followed by daylight, gives that clock a clear signal every morning.

If you only change one thing, change this.

Watch the timing of caffeine

Caffeine lasts longer in the body than many people assume. In a 2013 study in the Journal of Clinical Sleep Medicine, Drake and colleagues gave 12 healthy sleepers a large 400 mg dose of caffeine or a placebo at bedtime, three hours before, or six hours before. Even when taken six hours before bed, caffeine reduced objectively measured sleep by more than an hour. Strikingly, the participants’ own sleep diaries underestimated how much sleep they had lost.

The study was small and used a large dose, so the exact numbers should not be over-applied. But the authors concluded that it supports avoiding substantial caffeine for at least six hours before bedtime, which matches NHS advice to avoid tea and coffee for at least six hours before bed. If you go to bed at 11 pm, that means a mid-afternoon cut-off. Remember that tea, cola, energy drinks and some chocolate contain caffeine too.

Be honest about alcohol

Alcohol is often used as a sleep aid, and it does make many people drowsy. The research shows why that is misleading. A 2013 review in Alcoholism: Clinical and Experimental Research by Ebrahim and colleagues found that alcohol shortens the time it takes to fall asleep at all doses studied, but increases sleep disruption in the second half of the night. It also delays and, at moderate and higher doses, reduces REM sleep.

So a nightcap may help you drop off, then leave you waking at 3 am. Both the CDC and the NHS advise against alcohol close to bedtime.

Move during the day

Regular exercise is one of the better-supported habits. A 2015 meta-analysis in the Journal of Behavioral Medicine by Kredlow and colleagues, drawing on 66 studies, found that regular exercise had small benefits for total sleep time and sleep efficiency, small-to-moderate benefits for how quickly people fell asleep, and moderate benefits for sleep quality.

You do not need intense training. Daily walks and movement snacks all count. On timing, the NHS suggests avoiding exercise in the four hours before bed, though people differ; if evening workouts do not seem to disturb your sleep, there is no need to give them up.

Make the bedroom easy to sleep in

The CDC recommends a bedroom that is quiet, relaxing and cool. The NHS adds dark, with comfortable bedding. These are simple and low-cost: blackout curtains or an eye mask, earplugs if you live somewhere noisy, a slightly cooler room, and a bed that is used mainly for sleep.

Give screens an earlier bedtime

The CDC suggests putting screens away at least 30 minutes before bed, and the NHS advises against using them right before sleep. The National Institute of General Medical Sciences notes that light from electronic devices at night can confuse your biological clock. There is also the simpler problem that phones are designed to keep us engaged. Charging your phone outside the bedroom is one of the easiest changes to make.

Wind down, and go to bed when sleepy

The NHS suggests relaxing for at least an hour before bed, for example with a bath or reading, and going to bed only when you feel sleepy. A wind-down routine signals that the day is over. If your mind races at night, slow breathing can help you settle; our guide to breathing to calm down covers a few simple techniques.

Be careful with naps and late meals

The NHS lists daytime naps and big meals late at night among the things to avoid when you are struggling with sleep. The CDC also recommends avoiding large meals close to bedtime. If you nap and sleep well at night anyway, there is no need to worry. If nights are a struggle, it is worth trying a week without naps to see whether it helps.

When sleep problems are more than habits

Chronic insomnia

If you regularly struggle to fall asleep or stay asleep for months, and it is affecting your days, you may have chronic insomnia. This is common, treatable, and not a personal failing.

In 2016, the American College of Physicians published a clinical guideline recommending cognitive behavioural therapy for insomnia (CBT-I) as the first treatment for adults with chronic insomnia. CBT-I combines changing unhelpful thoughts about sleep with behavioural techniques such as sleep restriction (temporarily limiting time in bed to consolidate sleep) and stimulus control (using the bed only for sleep and getting up when you cannot sleep), alongside sleep hygiene education. The ACP noted that CBT-I is likely to have fewer harms than sleeping pills.

The NHS says GPs may offer CBT, either face to face or through an online self-help programme. It also says GPs rarely prescribe sleeping pills for insomnia because of serious side effects and the risk of dependence, and when they do, it is usually only for a few days or weeks.

Techniques like sleep restriction are best done with guidance from a trained professional or a structured programme, rather than improvised on your own.

Other sleep disorders

Sometimes poor sleep has a medical cause. The NHS notes that GPs may refer you to a sleep clinic if another condition such as sleep apnoea is suspected. Signs worth mentioning to a doctor include loud snoring, someone noticing you stop breathing or gasp during sleep, waking unrefreshed despite enough time in bed, or falling asleep during the day when you do not intend to.

Worry and low mood

Sleep and mental health are closely linked. Anxiety can keep you awake, and poor sleep can make anxiety and low mood worse. If worry is the main thing keeping you up, our guide to understanding anxiety explains what helps. If you are struggling with thoughts of harming yourself, call your local emergency number now, or a free crisis line such as 988 in the US and Canada or Samaritans on 116 123 in the UK and Ireland. Our crisis help page lists lines for other countries.

When to see a doctor

The CDC advises talking to a healthcare provider if you regularly have problems sleeping. The NHS suggests seeing a GP if changing your habits has not helped, if you have had trouble sleeping for months, or if your insomnia is making it hard to cope with daily life. Do not drive or operate machinery when you are very drowsy.

Putting it together

If all of this feels like a lot, here is a short version in order of priority:

1. Fix your wake-up time, seven days a week, and get some daylight soon after.
2. Set a caffeine cut-off at least six hours before bed.
3. Keep alcohol away from bedtime.
4. Move during the day.
5. Make the bedroom dark, quiet and cool, and move your phone out of reach.
6. If insomnia lasts for months, ask your doctor about CBT-I rather than relying on willpower or pills.

None of these steps is dramatic. That is the point. Good sleep is rarely the result of one perfect trick. It comes from a handful of steady habits that give your body clock a clear rhythm, and from asking for help when habits are not enough.