Jhe spring and summer months can make it impossible to sleep, with everything to contend with from sweltering temperatures and noisy late-night barbecues to raucous birdsong and early sunrises. Numerous studies have shown that our sleep deteriorates when spring arrives. Being stressed about it won’t help – although, of course, it’s understandable to be concerned about the climate crisis which will see our temperatures reach extremes and make it even harder to sleep.
But on a sleepless night, try to relax. “It’s completely normal to have a bad night once in a while,” says Dr Allie Hare, sleep consultant at the Royal Brompton Hospital in London. “Accept that if there’s a major heat wave, you might have a few nights that aren’t as good, rather than getting really anxious about it and then trying to sleep. As soon as you try sleep, you will not sleep. (If insomnia “has been going on for more than two weeks, it’s important that people see their GP,” she adds.) Here, experts give their tips for better sleep during the summer months.
Consider your circadian rhythm
“We all love those long evenings, but getting light exposure late can alter your circadian rhythm, cause what’s called a delayed sleep phase, and make you want to go to bed later than you otherwise would,” explains Guy Leschziner, professor of neurology and sleep medicine at Guy’s Hospital in London, and author of The Nocturnal Brain. “Obviously a lot of people have normal lives and they don’t want to sit behind closed curtains.” One way to balance it out is to get some bright light in the morning, “as soon as possible after waking up,” which should later in the day make you want to sleep earlier. Remember that bright light from screens, all year round, also has a negative effect on our sleep-wake rhythm.
The right light
Blackout blinds or curtains can be helpful if your room gets a lot of light early in the morning. An eye mask can also help, if it doesn’t make you too hot and sweaty. Your bedroom, says Hare, “doesn’t have to be completely dark. People can get a little obsessed with blocking out every burst of light. It is simply a matter of dimming the lights at the onset of sleep to allow your melatonin levels to rise [the hormone associated with sleep], then by reducing the significant light intrusion in the morning. You are more likely to wake up if there is a lot of light intrusion.
Reduce your room temperature
For most of us, says Leschziner, “the best room temperature in the bedroom is 16-18C (61-64.5F).” In a heat wave, he recommends draping a damp cloth over a fan, “because, essentially, the evaporation of the water from the dampened cloth will cool the air that the fan is blowing on you.”
Take a lukewarm shower or bath
“We know that our core body temperature and sleep initiation are closely linked,” says Leschziner. “In preparation for sleep, our core body temperature tends to drop. Before we wake up, it rises, so there are likely important regulatory mechanisms that link our core body temperature and our sleep. A lukewarm or just lukewarm bath or shower about an hour before bed “causes the blood vessels in your skin to dilate so that when you get out of the bath you can lose heat more efficiently.” Others advise against taking a cold shower before bed, yet tempting in hot weather, as it can actually raise your body temperature. “There is a scientific rationale, as a cold shower will cause your blood vessels to constrict and therefore make you less able to lower your core body temperature. So theoretically, yes,” says Leschziner, but he adds that he is not aware of any valid evidence.
keep a cool head
“The brain doesn’t like to get too hot,” says Jim Horne, Emeritus Professor of Psychophysiology at Loughborough University and author of Sleeplessness. It’s one of the reasons your cheeks turn red, especially when you’re tired, he says, because “your body is giving off heat.” You can open a window, but it may let in noise and light (if a breeze disturbs the curtains). Horne recommends a fan, which comes with the bonus of white noise – something many people find comforting. “A nearby fan with a gentle breeze overhead is, I think, the best method. It doesn’t matter if your body gets too hot while you sleep, as long as your brain stays cool.
Leschziner has heard them all. “People try to put a pillow in the fridge or even the freezer before they go to bed. Wear clothes that wick sweat away from your skin, as this increases the surface area from which your sweat can evaporate. And things like natural materials for sheets. This is all anecdotal, he says, but “anything you can do to try and cool yourself down a bit is something that’s probably going to facilitate better quality sleep.”
Stick to a routine
In the summer our schedules can change, from gardening at dusk, to eating late or hanging out with friends, and a light evening lulls us into the idea that it is still daylight, which means we go to bed later and later. . “A regular bedtime and wakeup time is, of all the things I recommend for good, stable sleep, probably the most important,” says Hare. Our habits also change – we can drink more alcohol, for example. “Alcohol helps you fall asleep because it’s a sedative, but it disrupts your REM sleep,” says Hare. “You’re more likely to wake up early in the morning and struggle to get back to sleep.” We may be more likely to eat later too, but Hare says we should try to avoid eating a large meal within two hours of bedtime “because your body can’t sleep and digest.” [at the same time]. Often you will have issues with reflux, indigestion and bloating, and this can disrupt your sleep. A light salad is fine; a barbecue feast is not ideal. And avoid iced coffee in the afternoon. “There is major genetic variability in how quickly we process caffeine, but for most people it takes a long time, so the general rule I give is to avoid caffeine after lunchtime” , explains Hare.
Avoid the nap
A nap in the shade is fun, but Hare says she doesn’t recommend napping, likening it to a snack between meals. “You’ll tend to have trouble falling asleep, wake up a little early, or not be able to maintain sleep because you’ve just reduced your appetite,” she says. The exception, she says, is “if you’ve had very restricted sleep – particularly if you have to drive somewhere or do something that involves a lot of concentration – then taking a nap is important because it improves your alertness and your ability to concentrate. But, generally speaking, I don’t recommend naps as a routine practice. There is evidence that they actually disrupt your sleep rather than improve it.
Sleep alone (maybe)
You may find that you sleep better without your partner tossing and turning with their own sleep difficulties or giving off heat. It’s “tricky,” says Hare, pointing out that sleeping with a partner is, for many people, an important part of their relationship; it’s often what the people she sees in her clinic want to come back to. “If you find that sharing the bed makes you both too hot, then yes, but I generally don’t like to advise sleeping apart,” she says. “It can be hard to go back to co-sleeping if you get into the pattern of sleeping separately.”
Don’t exercise too late
During the summer, you can try to adapt your running in the evening when the temperature has cooled down a bit, but this could make it harder to sleep. Vigorous exercise will raise body temperature, and the excitement and motivation of trying to beat your personal bests won’t help. Save it for the morning; in the evening, Horne recommends “a relaxing walk, in not too bright light.” Although he also adds that – like most of this advice – it’s for those who are vulnerable to fragmented sleep. “If you sleep well, do what you want.”