In short: Go to bed and get up at about the same time every day, including at the weekend. Adults usually need 7 to 9 hours. A sleep cycle lasts about 90 minutes.
Regularity beats even sleep duration
Tip: Get up at about the same time every day.
In a large British study, sleep regularity predicted the risk of death better than sleep duration alone. A fixed wake-up time is the strongest anchor for your body clock.
How to apply it: Choose a wake-up time and keep to it seven days a week, within about 30–60 minutes.
Source: Windred et al., 2024, Sleep.
You can’t pay off sleep debt in one weekend
Tip: Better to sleep enough every night than to only “recover” at the weekend.
In an experiment, restricting sleep on weekdays with lie-ins at the weekend still caused metabolic problems. Chronic sleep loss is hard to make up in a short time.
How to apply it: Add 30–60 minutes on weekdays by going to bed earlier. Avoid several late nights in a row.
Source: Depner et al., 2019, Current Biology.
Do you actually know how much sleep you need?
Tip: Test it: sleep for a week without an alarm on holiday and see how long you sleep on average.
For most adults, 7–9 hours is suitable. True “short sleepers” are extremely rare. Most people who think they can manage on 5 hours have a sleep deficit.
How to apply it: After the first days of catching up, you see your natural sleep need. Plan that many hours in bed.
Source: Watson et al., 2015, Sleep (AASM/SRS). He et al., 2009, Science.
Count in cycles of 90 minutes
Tip: Plan your sleep in cycles of about 90 minutes (for example 6 or 7.5 hours).
A sleep cycle lasts 90 minutes on average, although it varies. Deep sleep comes mostly early in the night, REM sleep mostly later. A night that is too short mainly costs you REM.
How to apply it: Count back from your wake-up time and add 15 minutes to fall asleep. If you only have 6 hours, that is better than 6.5 hours with a restless ending.
Source: Carskadon & Dement, Principles and Practice of Sleep Medicine.
Daylight saving time: prepare
Tip: In the week before the change, go to bed 15 minutes earlier every day.
In an American study, hospital admissions for heart attacks were about 24% higher on the Monday after the switch to summer time, and about 21% lower on the Tuesday after the switch to winter time. The total over the whole week did not change: it is mainly about timing. So your body does notice one hour’s difference.
How to apply it: Start 4 days beforehand, avoid late meals and alcohol, and get daylight outside on the Sunday.
Source: Sandhu et al., 2014, Open Heart.
Reducing jet lag: use light
Tip: Use daylight and the timing of light to shift your clock.
Jet lag research shows that the timing of light, and possibly melatonin, shifts your clock. After travelling east you need morning light, after travelling west evening light.
How to apply it: Adjust your sleep time a few days before departure. On arrival, eat, sleep and go outside on local time straight away.
Source: Waterhouse et al., 2007, The Lancet.
Night shifts: your body isn’t made for them
Tip: Working night shifts? Make sure you have a dark bedroom and fixed sleep times, and talk to your doctor about your health.
Shift work disrupts your clock and is linked to sleep problems and health risks. IARC classified night work as “probably carcinogenic”. The risk is greatest with long-term night work.
How to apply it: Wear sunglasses on the way home, use blackout curtains and keep your sleep time after the shift as fixed as possible.
Source: Kecklund & Axelsson, 2016, BMJ. IARC Monographs Vol. 124, 2019.
A nap before the night shift helps
Tip: Take a short nap before or during a night shift.
A review of shift workers showed that short naps reduce sleepiness and improve performance.
How to apply it: Plan 20–30 minutes around the middle of the shift, and let your colleagues know you are unavailable then.
Source: Ruggiero & Redeker, 2014, Biological Research for Nursing.
Morning or evening person? It’s in your genes
Tip: Get to know your own rhythm and schedule demanding tasks in your best hours.
Hundreds of genetic variants are linked to your chronotype. You can shift your rhythm a little with light and regularity, but not change it completely.
How to apply it: An evening person? Seek morning light, do not eat too late and schedule creative work as late as possible.
Source: Jones et al., 2019, Nature Communications.
The first night in a new bed is always bad
Tip: Take your own pillow when travelling and expect the first night to be lighter.
On the first night in a new place, the left half of the brain stayed more alert, a kind of “night watchman”. That usually disappears after the first night.
How to apply it: Do not plan an important appointment the morning after the first night and bring a familiar ritual with you.
Source: Tamaki et al., 2016, Current Biology.
Your sleep tracker can make you anxious
Tip: Use a tracker for trends over weeks, not as a verdict on one night.
Orthosomnia is the phenomenon of people getting stressed by their sleep score, which makes them sleep worse. Trackers estimate sleep and can be wrong.
How to apply it: Look at it at most once a week and pay attention to how you feel during the day, not just the score.
Source: Baron et al., 2017, Journal of Clinical Sleep Medicine.
Did you know?
A week of camping moves your clock earlier
A week in nature (sunlight, no artificial light) moved participants’ internal clock about 2 hours earlier.
Tip: Go outside for 15–30 minutes every morning, with sunlight in your eyes.
Source: Wright et al., 2013, Current Biology.
A rare gene lets some people sleep short
A mutation in the DEC2 gene lets a few families manage on 6 hours, but that is extremely rare.
Tip: “I manage on 5 hours” is almost never true. Test it by sleeping in for a week.
Source: He et al., 2009, Science.
We used to sleep in two parts
Historical research points to a ‘first and second sleep’ before the industrial era, with an hour awake in between.
Tip: Waking briefly at night is normal. Stay calm and do not look at your phone.
Source: Ekirch, 2001, American Historical Review.
And your mattress?
A fixed rhythm works best when your bed is right too. See the best sleeping position for your body.
Frequently asked questions
How much sleep do you need?
Most adults need 7 to 9 hours a night. How much you need yourself, you can tell from how rested you feel during the day.
Can you catch up on sleep at the weekend?
Partly. Sleeping in at the weekend does not undo all the effects of sleep loss and shifts your rhythm, which causes social jet lag.
More sleep tips
- Falling asleep faster
- The ideal bedroom
- Power nap and daytime tips
- Food, drink and sleep
- Worrying and insomnia
- Sleep and your body
- Sleep in the family
- Sleep, work and performance
- Effects of sleep deprivation
- All sleep tips
General information, not medical advice. If you have persistent sleep problems, snore with breathing pauses or are very sleepy during the day, see your GP. SleepLab One is not a medical device. Updated on 22 October 2026.
Social jet lag makes you heavier
Tip: Keep the difference in bedtime between workdays and days off small.
The bigger the difference between your sleep times on workdays and free days, the higher the BMI on average. In effect you live in a different time zone every weekend.
How to apply it: Set your alarm at the weekend too, at most an hour later than on weekdays.
Source: Roenneberg et al., 2012, Current Biology.