Sometimes, the best way to get through the day is by avoiding mirrors. You know you look tired; dabs of paste-like concealer, strategically applied teabags and visine can only do so much to combat the physical marks of exhaustion. The least-slept among us, however, may not look as haggard as they think. Insomniacs, according to a new study published in the Journal of Sleep Research, rate their faces as appearing considerably more weathered than they actually look. Seeing themselves as they really are may not take much more than know-it-all friends to point out the errors of their self-loathing ways.

Sleep loss doesn’t help people see the world more clearly. Quite the opposite — research depicts sleep-starved people as likely to misinterpret both cues from the outside world and their own behavior. For example, pulling all-nighters corresponds with tendencies to rate neutral language and facial expressions as negative. And, insomniacs tend to mis-report their sleep habits and difficulties, often underestimating how much they sleep and overestimating how long it takes them to fall asleep.

Knowing that insomniacs both misjudge other people’s facial expressions and exhibit exaggerated beliefs about their own sleep struggles, UK researchers at the Northumbria Center for Sleep Research sought to see if insomniacs could accurately assess how tired they looked. Spoiler alert: They couldn’t. Not only did insomniacs believe they looked rougher than they did; well-slept people saw themselves as looking more alert than they did.

When we assess how tired someone looks, we focus primarily on the eye area, study authors explained in their paper. In fact, research suggests that a handful of eye-centric facial characteristics motivate the universally appreciated comment “you look tired.”

The first characteristic is pretarsal show, which refers to the amount of skin visible between the eyelid and eyebrow. When people are tired, their eyelids hang, leaving more of this skin exposed. Along the same lines, we notice increased upper eyelid depression, meaning a higher-than-normal amount of eyelid skin is showing. We also infer tiredness from eyebrow elevation — how raised one’s Delevingnes are — and dark undereye circles.

But researchers found that people primarily use the first two facial characteristics  — more eyelid skin, more above-eyelid skin — to determine when a face needs its pillow. To figure this out, they used plastic-surgery editing software to manipulate a photo of a neutral face to emphasize only one tiredness cue. So, in one image, the face looked neutral aside from highly visible eyelids.

Then, they asked 44 people to rate how tired the face in each manipulated image appeared. Across the board, people rated images heavy on pretarsal skin and eyelid skin as evincing exhaustion. “Bleary-eyed,” it turns out, is a scientifically apt turn-of-phrase.

They didn’t manipulate undereye circles, as they explained in the paper, because dark circles show up more quickly and obviously in some of us, while eyelids droop in a more predictable manner.

Next came the self-judgment phase of the study. Researchers recruited two groups of young adults: clinically diagnosed insomniacs and healthy sleepers. First, participants (mixed in sex but female-heavy) sat for “neutral” photos. They were told to remove all makeup and make neutral facial expressions. Researchers took every participant’s neutral photo and edited it four times by amplifying and minimizing the two tiredness characteristics. For each participant, they developed a spectrum of morphed photos that ranged from “extremely tired” to “extremely alert.”

Each participant then got the pleasure of staring at computer-generated simulations of their face at different stages of sleep loss. Based on the morphed photos, they rated how tired their faces currently looked, in real life, on a scale of -100 to 100, 0 being neutral.

Insomniacs overestimated their tiredness levels considerably, despite having unedited photos of themselves in front of them. The normal sleepers, on the other hand, rated themselves as looking slightly (but not as significantly) more alert than they actually did. Researchers gave participants their accuracy scores to make them aware of their misperceptions.

The next day, participants returned to take new photos (still sans makeup) and repeat the experiment. Insomniacs improved considerably in assessing how tired they looked, whereas normal sleepers did roughly as well as they did the first time.

The findings, study authors explained, suggest that insomniacs don’t have a clear grasp of how they look. But, awareness of their misjudgements help fix their distorted self-images.

If gaining awareness affects how insomniacs see themselves, it’s possible that improved awareness could help straighten out other sleep-related misperceptions, such as insomniacs' common belief they don’t log any sleep.

To confirm the value of awareness, however, researchers said they’d have to repeat the study on a larger scale.

Until then, go pull a 2002 Christina Aguilera and tell an insomniac they’re beautiful, no matter what they say or how much upper eyelid they show.