Too many screens before bed will have a negative impact on sleep (Image: Getty)
Watching TV, drinking coffee, doomscrolling on our phones and even sipping water can all have a negative effect on our sleep. Here the experts tell us what time we need to stop each habit in order to achieve the best quality kip.
Drinking water
Cut off o’clock: One to two hours before bed
Staying hydrated is essential but according to the experts it’s a good idea to drink most of your fluids early in the day as too much water before bedtime can cause nocturia, the need to urinate at night. One study showed that 76% of women and 69% of men in the UK, US and Sweden have nocturia episodes that wake them up at night.
“Aim to stop drinking fluids one to two hours before bedtime,” advises Dr Hana Patel (time4sleep.co.uk). “However, if you find yourself waking up in the night due to thirst or dehydration, a small sip of water will help.”
Using our phones
Cut off o’clock: One hour before bed
Surprisingly, one recent study, published in Sleep Medicine Reviews, shows that being on your phone at bedtime isn’t quite as bad as originally thought but, even so, the blue light your phone emits mimics daylight and can throw off your natural body clock.
Dr Lindsay Browning, sleep expert for andsotobed.co.uk, recommends switching off an hour before you try to sleep.
“Our brains need to be calm to fall asleep and if we spend the hour before bed on our phones there will be too much adrenaline and cortisol pumping through our bodies and keeping us awake,” she says.
“An hour’s gap allows our brains and bodies to calm down, so falling asleep is easier.”
Having sex
Cut off o’clock: Never
“For a good night’s sleep, have as much sex before bedtime as you like,” says Dr Deborah Lee (doctorfox.co.uk). That’s because research published in the Journal of Sleep Research has shown that having sex that leads to orgasm at night not only improves sleep quality but also reduces the time it takes to fall asleep.
“At orgasm, hormones such as oxytocin and prolactin are released, making you feel relaxed and in a pleasurable state,” explains Dr Lee. “Levels of the stress hormone cortisol are also reduced. All of this is conducive to good sleep.”
Eating
Cut off o’clock: Three hours before bed
“Food and sleep have a very complex relationship, with poor sleep affecting food choices. Also, what and when we eat affects sleep,” says Dr Browning.
“When we should stop eating before bed is also complex, depending on how much food we eat, and what we are eating. Eating a large meal right before bed can cause indigestion which disrupts sleep, so studies show you shouldn’t eat your evening meal within three hours of bedtime.
“However, a light snack, especially those high in protein, tryptophan or melatonin, can promote sleep by reducing hunger and preventing low blood sugar.”
Caffeine
Cut off o’clock: 2pm
Research in the Journal of Clinical Sleep Medicine shows that even if you stop your caffeine intake six hours before you go to bed, it can still reduce sleep by more than
an hour. “That’s because caffeine has an average half-life of six hours which means that six hours after your cup of coffee,
half of the caffeine is still in your system,” explains Dr Browning.
“Caffeine is not only found in tea and coffee, but also in chocolate and some soft drinks. A 2pm cut off is a helpful guideline as it’s just after lunch and helps people remember to stop for the rest of the day.”
Listening to music
Cut off o’clock: Just before you doze off
You might think listening to music would keep you wide awake but research shows it can actually help you nod off. One study published in the Journal of Community Health Nursing asked women with insomnia to listen to their own playlist in bed for 10 nights and the results showed that doing so reduced the time they took to fall asleep from 27-69 minutes to just 6-13 minutes.
“This may be because listening to music causes the release of dopamine, the feelgood hormone, and also lowers cortisol levels,” says Dr Fox. “Music dampens down the autonomic (involuntary) nervous system, resulting in a lower heart rate, slower breathing rate and lower blood pressure.”
Alcohol
Cut off o’clock: Three hours before bed
Drinking alcohol can make you fall asleep more quickly but studies show that no matter how little of it you drink, it still reduces the amount of NREM (non-rapid eye movement) sleep, or lighter sleep, you get. It also increases your chance of suffering from sleep apnoea, which also disrupts sleep.
“Many people have issues staying asleep and getting good quality sleep after drinking so it’s always best to avoid alcohol three to four hours before bed,” says Dr Patel. “This is so your body has plenty of time to metabolise the alcohol and get it out of your system before you sleep.”
Chatting
Cut off o’clock: One to two hours before bed
It’s tempting to enjoy some pillow talk at bedtime but while this may help strengthen your relationship, sadly it could also be the reason you’re struggling to sleep.
“You need verbal and social media silence 1-2 hours before bedtime,” insists Dr Fox.
“You can only drift off to sleep when your brain is in a relaxed and peaceful state. This means winding down for sleep a couple of hours before bed.”
Exercise
Cut off o’clock: One hour before bed
“Research shows we should avoid vigorous activity for at least one hour before bedtime as it can lead to us taking longer to fall asleep, while also diminishing our overall sleep quality,” says Dr Patel.
One Harvard study suggests this is because intense exercise leads to physiological excitement and it then takes our brains and bodies time to settle back down. “High intensity workouts in particular should ideally be earlier in the day,” advises Dr Patel.
Being outside
Cut off o’clock: Two hours before bed
As summer finally sets in most of us can’t wait to enjoy those long, warmer evenings. But, according to Dr Fox, we should head inside long before bedtime.
“Wait at least two hours to go to bed after being outside in daylight,” she advises. “Your brain needs to take note of the arrival of darkness, or the absence of daylight, and become aware of a drop in air temperature. Darkness stimulates the production of the sleep hormone melatonin, which is vital for your body’s natural clock which governs your sleep-wake cycle. It takes around two hours to produce enough melatonin to give your body the correct signals it’s time for sleep.”
Watching TV
Cut off o’clock: One hour before bed
It’s common to watch TV to unwind in the evenings but, as with our phones, the blue light emitted can leave us feeling wide awake.
US research shows that binge watching in particular had an adverse effect as viewers took longer to switch off.
“Always aim to stop watching TV at least one hour before bedtime as this will help encourage REM sleep which is important for our overall health and immune systems,” advises Dr Patel. “When we’re in the REM part of our sleep cycle, our brains are truly resting and repairing themselves, while also processing any emotions from the day.”