Hopefully we don’t need to remind you of the importance of sleep. “Clean sleeping” was dubbed the biggest health trend of 2017 and lifestyle blogs and newspaper supplements have published a forest’s worth of articles about its benefits recently, so you probably know them by now.
But if you weren’t already convinced by the idea of a decent night’s kip, maybe the results of a new study will make you change your nocturnal ways by appealing to your vanity.
It turns out that “beauty sleep” – sleep that leaves us feeling healthy and attractive – is actually real, according to the research by Stockholm University, published in the journal Royal Society Open Science.
Just two nights of bad sleep is enough to make you look “significantly” more ugly and those who get less sleep are perceived as less appealing to hang out with, the study found.
To test the beauty sleep hypothesis, researchers asked 25 male and female university students to track the amount of sleep they were getting and had strangers rate photos of the participants afterwards.
The students were asked to get two nights of good sleep, followed by just four hours' sleep for two consecutive nights the week after. The researchers took makeup-free photos of them after each of the sleep sessions.
Another group of volunteers – 122 men and women living in Stockholm, Sweden – were then asked to rate the photos on attractiveness, health, sleepiness and trustworthiness. They were also asked: "How much would you like to socialise with this person in the picture?"
The volunteers were good at deciphering tiredness from the images, and those who were considered sleepy in their photos were deemed less attractive.
Tiredness could also make you less appealing to hang out with, the study suggested, with the volunteers saying they would be less willing to socialise with the tired students and perceiving them to be less healthy.
“Having an unhealthy-looking face, whether due to sleep deprivation or otherwise, might activate disease-avoidance mechanisms in others,” the researchers said. Basically, we don’t want to spend time with people who might be ill (charming!), which the team said makes evolutionary sense.
“Since sleep-deprived faces are both less attractive and less healthy-looking than their well-rested counterparts, they contain at least two perceptible features possibly impacting others' willingness to socialise with them.”
However, Dr. Tina Sundelin, who led the research, said she didn’t want to make people lose sleep over the findings. "Most people can cope just fine if they miss out on a bit of sleep now and again,” she told the BBC. The question is: is it worth the risk?