The arrival of shorter, darker days and a noticeable drop in temperature can significantly impact our daily energy levels, but winter’s effect on our sleep patterns can be even more disruptive.
From restless nights in a chilly bedroom to waking up feeling unusually groggy, cold weather presents unique challenges to achieving quality sleep.
Dr David Garley, a GP and director of The Better Sleep Clinic, says that colder weather and altered daytime activity can strongly influence sleep during the colder months.
“When you move from the wake phase to the sleep phase of your circadian rhythm, that’s marked with a drop in your core body temperature of about 0.5C to 1.5C,” he says.
“So, if you’re very hot, you may struggle to make that transition, and that is why many people struggle to sleep in the summer.”
However, while overheating can impede sleep, an excessively cold room can also pose a problem.
“You want your bedroom to be cool,” Dr Garley says.
“This exact temperature will be different for different people. You don’t want your room to be icy cold, but on the cooler side is definitely helpful.”
Can the cold affect your ability to get to sleep?
“If it’s really cold, then your body will be focused on maintaining temperature rather than slipping into sleep,” explains Dr Garley.
“For example, if you’re shivering in bed then you’re unlikely to fall asleep.
“In that situation, you do need to find ways to warm up your environment a bit.”
Can the cold affect sleep quality?
“People often only think about the number of hours they’ve slept, but it’s also important to think about whether you reach those deep stages of sleep,” says Dr Garley.
“If you get what we call these ‘arousals’ from sleep [such as extreme or sudden coldness], they won’t always necessarily wake you up entirely, but they can pull you into the lighter stages of sleep which are less refreshing.
“So, if your body has shifted focus to maintaining body temperature, you may find that you have shallower sleep or actually wake up.”
This happens a lot while camping, for example.
“Campers often find that around 3am in the morning, when there’s that real temperature drop, that they wake up and feel absolutely frozen solid,” says Dr Garley.
Can winter-related illnesses disrupt sleep quality and quantity?
“If you have got inflamed airways, your nose is running, you’ve got a cough and a sore throat you will probably find it harder to fall asleep,” says Dr Garley.
Also, these symptoms may increase your likelihood of snoring.
“A lot of people find that they only snore if they have got a cold or if they’ve got hay fever,” says Dr Garley.
“If your airway is a bit more swollen and a bit more narrow, you are more likely to snore more.”
Something like a common cold could also potentially worsen the symptoms of sleep disorders such as obstructive sleep apnoea.
“Sleep apnoea is a sleep disorder associated with snoring, where your upper airway repeatedly closes as you sleep and you get these pauses in your breathing which leads to really fragmented sleep,” explains the GP.
“So, if you’re already on the cusp of obstructive sleep apnea and then you get a cold, you might find that you actually do get clinically significant obstructive sleep happening with really fragmented and poor quality sleep.”
Can Seasonal Affective Disorder (SAD) affect sleep?
Mental health and sleep are closely intertwined.
“Anxiety can make it quite difficult to fall asleep and depression can cause early morning awakening, but research also shows that this actually works the other way around, too,” says Dr Garley.
“Research suggests that poor sleep can cause anxiety and depression, which means there’s a system which can feed into itself.
“Therefore, if you’re getting depressed as a result of seasonal factors, then that low mood can certainly impact your sleep.”
How else can cold weather impact sleep?
This seasonal change and wintry weather often alters people’s routines, which can have a knock-on effect to their sleep.
“The shorter, darker days mean that people often don’t go out socialising as much, stop exercising and/or aren’t getting that exposure to sunlight, and these factors are really important for maintaining good quality sleep,” says Dr Garley.
Top tips for improving your sleep this winter
Keep to a routine
“Despite it being darker and colder, do try to keep your routine as normal as possible,” advises Dr Garley.
“Don’t let the seasons push you around. You want to feel that you’re in the driving seat of your own life.”
Stay active
“When you exercise, you tend to build up a stronger drive for sleep at night,” says Dr Garley.
“If the cold, dark weather is stopping you, then try to find an indoor activity to keep that momentum going.”
Layer up in the night
“With temperature control and sleep, using layers can be quite good,” recommends Dr Garley.
“If you put an enormous duvet on at night, then you might wake up all sweaty in the middle of the night, so using multiple thinner layers can be a good way to manage that.”
Keep your room at a cool temperature
Find a temperature that works for you. “You want your bedroom to be cool, but not cold,” recommends Dr Garley.
Go for a walk
“Go outside into the daylight on your lunch break,” says Dr Garley.
“Getting that light dose is so important for maintaining that consistent circadian rhythm.”
Don’t force it
If you are struggling to sleep, get up and do a relaxing activity until you feel sleepy again, then return to bed.
“If you can’t sleep, try not to force it,” says Dr Garley.
“If you lie in bed and get annoyed, then that independently is going to stop you from sleeping.”
