A 50-year-old woman named Theresa Lynch nearly lost her one eye after not washing off her mascara for more than 25 years, reported the Daily Mail

According to Science Alert, the Australian woman went to the ophthalmologist complaining about eye problems. He then found horrifying black spots on the inside of Theresa's eyelids, all due to "a problematic beauty routine".

I'd say.

According to the Science Alert, some of the tiny bits of solidified mascara had started to poke "through the conjunctiva and scratching the woman's corneas, which was causing the discomfort."

Hopefully, none of us go that long without removing our makeup.

While sleeping with your makeup on for one night will unlikely cause long-lasting damage, Dr. Nomphelo Gantsho, a dermatologist, says, "each night you sleep wearing a full face of makeup can block your pores and glands, hindering your skin’s ability to breathe." And your skin needs to breathe for a number of reasons. 

READ MORE: 7 mascara tricks for longer and fuller lashes

Four main things happen when you sleep with your makeup on, says dermatologist, Dr. Mercedes Morrison: 

  • Certain ingredients in your makeup products may contain allergens. Although they may not cause overt reactions on the skin, overtime they may cause skin irritation. 
  • Sleeping with your makeup on may clog your pores and can cause acne breakouts and blackheads, especially if you are more prone to acne. 
  • Sleeping with your makeup on can make your skin a breeding ground for bacteria, which can cause infections, especially around sensitive areas like your eyelids. 
  • Sleeping with your make up on can age you faster. The chemicals in makeup can result in free radicals which are unstable molecules. These unstable molecules damage the collagen in the skin which will then result in wrinkles. 

Here's a breakdown of what happens when you sleep with specific makeup products on:

What actually happens when you sleep with mascara on?

"Mascara traps dust and bacteria and that is kept close to your eye. Particles of the mascara can be very irritating for your hair follicles, and can even go as far as to clog them and cause inflammation of your eyelid and even conjunctivitis," says Dr. Gantsho. So if you care about the health of your eyes wash your mascara off. 

A little foundation to bed is too much foundation 

Dr. Gantsho says, sleeping with makeup such as foundation has been linked to skin discolouration and the breakdown of collagen due to the free radicals from the environment trapped on the makeup. Foundations and oil-based primers are some of the products that trap free radicals onto our. They prevent the skin from renewing itself naturally at night, causing breakouts, blackheads and skin irritation, she explains.

READ MORE: 4 foundation fails a makeup artist wants you to stop making right now

What happens when you sleep with lipstick on? 

If your lipstick offers you moisture during the day it won't necessarily offer you moisture throughout the night. According to Dr. Gantsho, "lipsticks have drying waxes that can lead to chapped lips after prolonged overnight wear." Although it sounds worrying, Dr. Gantsho explains that, "lips recover quickly, so you can worry about them last if you’re really too tired."

In general, sleeping with makeup on is a big, resounding "NO!"

Dr. Gantsho emphasises that sleeping in makeup is a terrible idea. "Our skin is bombarded with dust and dirt throughout the day, and much of it sticks to the make-up and sebum in our skin. Leaving all that on overnight will damage the skin," she explains. So don't do it. 

If you don't want to age too fast you might want to start adopting healthier skin care routines. Here are some tips from her to help you care for your skin: 

  • Use makeup remover to remove the makeup if you have the time and you are not tired. Don’t rub your face as this can lead to irritation, just gently wipe away. Wash your face afterwards with a facial wash and follow with a moisturiser to soften your skin. 
  • If you have sensitive skin, you can remove your makeup using micellar water and cotton wool.
  • If you have had a long day and you are tired, use makeup wipes. You can even remove the makeup while in bed.

READ MORE: The one anti-ageing product everyone can afford

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