20 May, 2017
Are you skipping your beauty sleep? And that's not all.
The volunteers photographed themselves, make-up free, after getting a good night's sleep for two consecutive nights before taking pictures once again after only having four hours sleep for two nights in a row the following week.
122 volunteers (65 women, 57 men) aged between 18 to 65 were then asked how much they would like to socialize with the person in the photo.
"Findings show that acute sleep deprivation and looking exhausted are related to decreased attractiveness and health, as perceived by others", the study authors conclude.
While the scientists acknowledged that attractiveness may have little to no connection with actual health, "faces that look healthy are also considered attractive".
The study found that after only two nights of shorter-than-normal sleep, people are not only viewed by others as being less attractive and less healthy than after they are fully rested, they are also seen as less appealing to socialize with. After that, they were photographed by the researchers. The Royal Society Open Science journal also found people viewed the more worn out individuals as less attractive.
But lead researcher Dr Tina Sundelin added: "I don't want to worry people or make them lose sleep over these findings".
While further studies are needed to gain a better understanding of the mechanisms underlying the effects of sleep deprivation on facial appearance, the researchers believe that their findings further highlight the importance of a good night's sleep.
Whilst there was no difference in perceived trustworthiness, the study suggested that "naturalistic sleep loss can be detected in a face and that people are less inclined to interact with a sleep-deprived individual".
However, statistics show that around 1 in 3 adults in the United States fail to get the recommended minimum of 7 hours of sleep each night.
This makes a lot of sense in evolutionary terms.
"People seem to be able to tell when someone needs more sleep, and are more inclined to leave them alone in that case", the authors wrote in the new work. Because we've evolved to try to avoid diseases, seeing an unhealthy-looking face makes us want to avoid that person.