Sleeping With Makeup On and 5 Other Habits a Dermatologist Flags

I'm Dr. Hongseok Kim, a board-certified dermatologist with 21 years of practice and the medical director of VOS Dermatology Clinic in Gangnam, Seoul, right in front of Dosan Park. I see every patient myself, from the first consultation to the treatment.

Sleeping with makeup on is the first of six everyday habits I asked viewers to be honest about in this video, because as a Korean dermatologist I keep meeting people who do these things without realising what they cost their skin. If you fix even one of them, the money and effort you spend on cleansing and products will work better. This page is based on my YouTube video from December 2023; I rewrote it for readers abroad. The video above can be watched with translated captions.

Habit 1: going to bed without washing, especially with make-up on

Washing before bed is non-negotiable, because sleeping with makeup on traps oil under blocked pores.

I was genuinely surprised to hear how many people go to sleep without washing simply because they are tired (in the video at 00:24). This matters most if you wear make-up (in the video at 00:43). Your skin keeps producing sebum through the night, but when the pores are covered, it has nowhere to go. That is exactly the condition that produces tiny bumps, comedones and acne-like lesions. On difficulty, I give this one the lowest score: anyone can do it, so everyone should pass.

Habit 2: leaving a sheet mask on too long, or overnight

A sheet mask left on past its time weakens the skin barrier instead of helping it.

Think of soaking your hands or feet in water for 15 or 20 minutes: the skin swells (in the video at 01:04). Swollen skin means the barrier is breaking down. Some masks are rich enough that people leave them on for a long time, but the longer the skin stays wet, the weaker the barrier becomes. Bacteria on the skin can then get in and cause inflammation, such as small bumps, and the skin can turn soft and fragile.

Some people even sleep with a mask on (in the video at 01:46). As it dries, the water evaporates and pulls moisture out of your skin with it, so the skin ends up drier or more sensitive than before. Keep to the time on the package and never leave a mask on overnight.

Habit 3: touching your face, and your phone

Touching your face repeatedly disturbs the balance of bacteria that naturally live on your skin.

Your skin hosts many different microbes, and the mix differs by area (in the video at 02:27). Oily areas such as the face, chest, back and scalp carry bacteria that like sebum; drier areas carry others. When your hands or other objects keep moving from one environment to another and onto your face, that distribution changes. For people whose skin barrier is already weak, the repeated contact makes it easier for the balance to collapse.

Phones are a good example (in the video at 03:10). We carry them all day, put them in bags and press them to our cheeks, but few people ever clean them. Since you cannot wash your hands every few minutes, the most practical rule is simply to keep your hands off your face.

Habit 4: over-cleansing until your skin squeaks

If your face feels tight after washing, the cleanse has already damaged your skin barrier.

That tight feeling means the lipids that build the barrier, such as ceramides, cholesterol and fatty acids, have been washed away (in the video at 03:55). Many people have over-cleansed all their lives, so their dry, damaged state has become their normal, and changing moisturisers alone does not help. That is why I recommend a 60-second wash (in the video at 04:51). With no make-up, finish within one minute. With make-up, spend one to two minutes removing it and then 60 seconds on a second wash with a foaming cleanser, staying under three minutes in total.

If you used a heavy, hard-to-remove sunscreen, a mineral sunscreen or oily make-up, use a cleansing oil or cream first and concentrate on removing that quickly (in the video at 05:12). And if residue keeps staying behind even then, change the product (in the video at 05:52). A product that forces you to over-cleanse keeps your skin sensitive. My notes on how to calm sensitive skin go into cleansing for reactive skin in more detail.

Habit 5: not changing your pillowcase

Your face spends about eight hours a night on your pillowcase, so change it at least once a week.

Many people change it rarely, and some leave the same one on for six months (in the video at 06:24). However carefully you cleanse, a dirty pillowcase puts your clean face back against whatever has built up on it. I noticed this myself with a vitamin C powder: ascorbic acid oxidises easily and turns slightly yellow, and after applying it every night my white pillowcase slowly turned yellow (in the video at 06:53). Much of what you apply is absorbed, but a fair amount ends up on the pillowcase. That is why I believe the pillowcase, at least, should be changed once a week (in the video at 07:58). Use a white one so you can see when it needs washing.

Habit 6: squeezing breakouts by hand

Squeezing a breakout hard usually pushes inflammation deeper and can leave pigmentation behind.

Patients come to me with skin broken and stained after squeezing until nothing more would come out (in the video at 08:42). Compared with a single skin cell, the pressure of your fingers is enormous (in the video at 09:23). Pressing hard ruptures surrounding cells, which triggers more inflammation, and more of the contents is pushed inwards than out. Skin cells contain melanin, and when many of them burst at once, post-inflammatory pigmentation often follows (in the video at 10:04). If a spot has come to a head, opening the surface slightly and pressing very gently is enough; a patch with AHA or BHA can help calm it. Squeezing with two cotton buds is still squeezing. I rate this the hardest habit to break, and the most important.

A firm, red bump with no pus should not be touched at all (in the video at 11:04). That is papular acne: inflammation packed deep in the skin that will not come out however hard you press. The quickest way to settle it is an injection into the lesion, or oral or topical medicine prescribed by a dermatologist. My guides on Korean acne treatment options and when to wait before clinic treatment with active acne explain what a clinic can do, and which ingredients calm acne-prone skin covers the home side.

If your skin still feels congested after you fix these habits, a gentle clinic cleanse such as HydraFacial, which exfoliates and hydrates without lasers or injections, is one option some patients ask about; my overview of what a Korean HydraFacial involves explains it, and you can read creator experiences at VOS. Before booking, send us on WhatsApp a daylight photo without make-up.

Results vary from person to person, and what your skin needs is decided at a consultation.

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Results, swelling and recovery vary from person to person. This page is general information from VOS Dermatology Clinic based on Dr. Kim's video and does not replace an in-person consultation.