Carrying on camping! The health benefits of sleeping under the stars
Sleeping outside is more popular than ever, if Instagram is anything to go by.
More than 36 million posts on the social media site are dedicated to camping, with users proudly showcasing their outdoor set-ups. Travel restrictions mean many are enjoying staycations for a second year, taking advantage of the pandemic to "explore their own backyard".
Lockdown is also said to have made people more appreciative of nature, with many keen to spend time outdoors.
Read more: Natural sounds reduce pain, ease stress and boost mood
Sleeping in the fresh air may sound idyllic, or perhaps hellish, but is it good for us?
"Outdoor sleeping can bring many benefits - on mood, exposure to fresh air and freedom from stress, artificial light and computer screens – put your mobile away too," Dr Sarah Brewer, head of nutrition at Healthspan, told Yahoo UK.
So-called forest bathing – or "shinrin-yoku" – is popular in Japan, defined as "making contact with and taking in the atmosphere of the forest".
Read more: Travel is good for you (here's to the end of the pandemic!)
"Communing with nature and green vegetation produces beneficial physiological changes whether you walk in a forest area, or simply sit or lie down to view the forest landscape," said Dr Brewer.
A 2010 Chiba University, China, study found walking around or simply "viewing" a forest reduces a person's blood pressure, as well as lowering their levels of the stress hormone cortisol.
"The sounds of nature can have a calming effect to help you fall asleep, especially if you can hear a babbling brook, gentle waves or wind rustling through leaves," said Dr Brewer.
These could be compared to white noise, with many relying on continuous whale or rainforest sounds to nod off.
Nevertheless, "it's important to remember noises in nature are not predictable so there could be some noises that interrupt your sleep too", Dr Daniel Atkinson, clinical lead at Treated.com, told Yahoo UK.
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While some relish their home comforts, a change of scene in itself could do wonders for your wellbeing.
"Taking advantage of being outdoors can provide the opportunity to take our minds away from our daily worries," said Dr Atkinson.
"If you spend the night outdoors in an area that has good quality, clean air then your breathing may benefit too."
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A sleeping bag on hard ground may not sound relaxing, but spending the night outdoors could help to synchronise our body clock to the rise and fall of the sun, aiding shut-eye.
"Secretion of melatonin hormone, our natural sleep hormone, increases as natural light falls and is suppressed as the sun comes up," said Dr Brewer.
"Artificial light interferes with these natural rhythms, which are regulated by the suprachiasmatic nuclei in the [brain's] hypothalamus, which is trained to the sun's rise and setting via light detection in the [eye's] retina."
Writing in the journal Somnologie, medics from the University of Basel in Switzerland have warned "nocturnal light has been shown to alter circadian [internal] rhythms and sleep in humans".
A team from the University of Colorado Boulder also reported being exposed to just natural light synchronises a person's "internal circadian clock to solar time", causing their "internal biological night" to occur at sunset and end "before wake time, just after sunrise".
What's more, the benefits may be almost instant.
"Even just two nights spent sleeping outdoors per year could be seen to have some benefit," said Dr Atkinson.
"Waking up naturally because of the morning sunlight can be a pleasant way to wake up, which could leave you feeling more refreshed and ready for the day ahead," he added.
"The sun rises earlier in the summer too, so be prepared for an early wake up call," said Dr Atkinson.
Safety first
For those sold on a night under the stars, Dr Brewer has stressed people should do their research, opting for "somewhere private and safe".
Take a companion if you can, "as you don't want to lie awake fearful of prowlers or wild animals", she added.
Solo sleepers should let someone know where they are.
"Perhaps check the area has phone signal and you have enough battery for any just-in-case moments," said Dr Atkinson.
"The exact spot you choose to rest your head should be away from any potential natural dangers, for example wildlife, livestock, cliff edges or water."
Staying away from water also reduces the risk of being bitten by mosquitoes, however, insect repellent is still recommended. People with allergies, particularly hay fever, should also pack anti-histamine tablets.
If forgoing a tent, ensure you have sunscreen to hand, which is also a must when exploring during a summer's day.
Check the weather forecast in advance. A tent may be a good backup in case of unexpected rain.
Even during the warn months, several blankets are usually required at night.
"At the height of British summer time, the night time temperature can still drop and leave you feeling chilly," said Dr Atkinson.
"Thin layers can help to regulate your temperature, plus you can remove them should you need to."
A waterproof ground sheet, and cover if using a tent, also prevent dew from drenching clothing or bedding.
Watch: Stay safe from severe weather while camping
