On the most hectic days, sleep pulls rank over just about everything, including — but not limited to — food, laundry, literally anything on your to-do list, and certainly proper skincare. Because when you’re super tired, it’s damn near impossible to conjure up the energy to wash your face before bed. What’s the worst that can happen, right? Weeell, your skin will be in for a pretty rough night.

“Dirt, oil, makeup, particles from the polluted environment, and dead cells accumulate on the skin during the day,” explains Joshua Zeichner, MD, director of cosmetic and clinical research in the department of dermatology at Mount Sinai Medical Center. “If you don’t wash your face in the evening, they remain on the skin’s surface, causing issues like dullness, dryness, or even more serious issues.”

These seven skin problems caused by sleeping in your make will ensure you never skip the face wash again.

MORE FROM BEAUTY

Get This New Year’s Eve Look: Grey Smokey Eyes + N

This Oil-Spill Eye Makeup Look Is So Dope

Watch Beauty Vlogger Toni Olaoye Talk The Power Of

1. DRYNESS

“Your skin’s natural hydration decreases in the evening as part of normal circadian rhythms,” says Zeichner. “If you have dirt, oil, and makeup interfering with the skin, it can’t maintain hydration properly.” That’s a recipe for a dry, flaky face that’s hard to plump back up with a simple pump of morning moisturizer.

2. DULLNESS

“The skin becomes dull when you have an accumulation of dead cells on the surface because it can’t properly reflect light,” says Zeichner. That’s why clean, freshly washed skin looks more radiant — “not washing your face allows for an accumulation of these dead skin cells.” That makes a pretty strong case for regular scrubbing, right?

3. INFLAMMATION

Your skin acts as a barrier against the environment, and when it’s healthy, it can regulate itself accordingly (think: your skin staying hydrated on a cold, dry day). But “when makeup, dirt, and oil are left on skin, they form a film that can interfere with the skin’s ability to maintain a healthy barrier,” says Zeichner. “The barrier, known as the stratum corneum, has a brick-and-mortar model — if the skin is the brick wall, the bricks are the skin cells and the mortar is made of lipids, a natural fat. When the barrier is disrupted, there isn’t as much mortar, which allows hydration to leak out and put the skin is at greater risk for environmental exposure.” All of this leads to inflammation, which can look like redness, itchiness, peeling, scaly skin, or a hot mess mix of them all.

4. ACNE

“Excess dirt, oil, sweat, and makeup accumulate on your face throughout the day and form a film on your skin,” says Zeichner. “The skin can’t breathe properly with this film over it, so oil and sticky cells build up underneath, forming blockages.” That’s when you’ll start seeing acne appear. It’s like the bathtub you’ve been meaning to clean for a few weeks now — soap scum builds up every day, making it a much harder (re: grosser) job to do when you finally get around to it.

5. STYES AND INFECTIONS

Yes, those annoying (and irritating) little bumps around your eyes can be caused by not cleansing at night. “Again, not adequately removing makeup can cause blockages of pores and glands around the eyes — and those could contribute to styes,” says Zeichner. Not cool. And if you have any sort of open wound (think: a cut or newly popped blemish), you could also end up with an infection. “Healthy skin can protect itself,” says Zeichner, but if bacteria has a direct line beneath the skin, all bets are off.

6. PREMATURE AGING

MORE FROM BEAUTY

Beauty Trends You Should Ditch In 2017!!

Watch Toni Oloye Speak On The Power Of Makeup.

These Are The Beauty Trends We’re Ditching In 2017

“Gases and dirt particles, or particulate matter, from smog and pollution can accumulate on the skin and get into your pores, which leads to free radical damage — inflammation and chemistry changes that can damage existing collagen, your DNA, and, in some cases, lead to an increase in pigment production, causing sun spots, dark marks, and irregular tone,” says Zeichner. Washing your face before bed shuts off the particulate matter faucet, so to speak, stopping buildup before it can cause all that damage, which tends to present itself as fine lines, wrinkles, crepe-y skin, pigmentation, and prominent pores — all things that can make you look years older than you really are.

7. DRY, CHAPPED LIPS

“The skin on the lips is among the most sensitive on the body,” says Zeichner, “and irritating ingredients in makeup may lead to inflammation of the lips if they’re in contact for extended periods of time.” Remember, inflammation means peeling and scales — not a cute look for your lips. “Just because your makeup says it lasts for 24 hours doesn’t mean you should wear it for that long,” he adds.