Those who have restricted sleep are less attractive to others, says a new study.
Compounding the idea of beauty sleep, new research shows that a couple nights' bad sleep is enough to make a person look "significantly" uglier. It can even put people off socialising with you, reports the BBC.
The Karolinska Institute researchers asked 25 students, some male and some female, to get a two good nights' sleep in a row. This was monitored with a kit that recorded their night-time movements. They were then asked to restrict themselves to just four hours sleep for two consecutive evenings. Make-up free photos were then taken of both scenarios.
The researchers next asked 122 strangers to look at the pictures and rate them on attractiveness, health, sleepiness and trustworthiness. They also asked them, 'How much would you like to socialise with this person in the picture?'
If the person looked tired, they were marked less on attractiveness. The strangers also said they would be less likely to socialise with the sleepy participants because they looked unhealthy.
'An unhealthy-looking face, whether due to sleep deprivation or otherwise, might activate disease-avoiding mechanisms in others,' say the researchers.
Dr Gayle Brewer, a psychology expert at the University of Liverpool and member of the British Psychological Association, said: 'Judgement of attractiveness is often unconscious, but we all do it, and we are able to pick up on even small cues like whether someone looks tired or unhealthy.
'We want our partners to be attractive and energetic. This study is a good reminder of how important sleep is to us.'
