You probably have lash mites. Here's what to know about symptoms and risks

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Have you ever fallen asleep with mascara on and wondered if it's really that bad to do so? We have — and then we saw a viral TikTok about lash mites.

Yes, they're real; they're microscopic parasites that live at the base of eyelashes.

To get a sense of what the risk of lash mites is, Yahoo Canada checked in with the president of the Canadian Association of Optometrists (CAO).

Read on for everything you need to know.

Context

• Lash mites resurface as a trending topic on TikTok every few months.

• One video by user @weloveeyesxo (self-identifying as 'eye care' content), went viral in May claiming the TikToker fell asleep with mascara and woke up with lash mites.

• Another video by user @katiehub.org included lash mites in a "reminder to take your mascara off before bed" and consequences "if you don't."

• Videos with the hashtag "lashmites" have been viewed more than 25 million times on TikTok.

What are lash mites?

Lash mites — known as demodex — are tiny parasites that have four pairs of legs and live in hair follicles on the face, neck and chest areas.

They're microscopic, meaning they're nearly impossible to see with the naked eye.

As CAO president Dr. Martin Spiro tells Yahoo Canada, lash mites are "pretty common" — nearly all adults will have them.

They develop over time.

"When we're a little younger, we have a little bit less," Spiro explained. "But as we get older, we tend to develop more and more to the point where, I believe, in people over 60 or 70, it's pretty ubiquitous that everybody has them."

It's not entirely known exactly how they form.

"They're either transmitted through the eggs in the air dust, or it's possible... since everybody has them, touching as kids and things like that," Spiro said.

Are lash mites dangerous?

According to the eye health expert, lash mites are harmless.

"It's not really something you're worried about developing," he said.

"These mites, for most for the vast majority of people, they're part of our makeup on our skin surface and hair surface," he added.

However, an overgrowth of lash mites can lead to problems.

Spiro explained demodex like to feed on material when eyes are not in their healthiest state, allowing them to multiply. This can happen when you fall asleep with makeup on.

"It's not that they just develop out of nowhere, and it was from the mascara. It's probably the fact that... because of the surface that was not very hygienic or, if they went to bed with the mascara or the makeup on, the [lash mites] had a little bit more food and multiplied a little bit more."

Lash mite overgrowth: Symptoms and treatment

Some people are more sensitive to an overgrowth of demodex, Spiro claimed.

One condition that could develop is blepharitis, which he said is a common condition where the eyelids are inflamed.

"That could be a result of overgrowth of [demodex] but also people who use a lot of computer screens and don't blink enough, or have a little bit more dry eye, also who tend to have rosacea develop."

With an overgrowth, the patient could also feel their eyes be "a little bit crusty, gritty."

But, Spiro said those symptoms could be caused by things other than lash mites, including an overgrowth of bacteria.

To know exactly what the cause of inflammation or odd texture is, it takes a professional assessment.

The expert said an optometrist would use a microscope to determine whether there was a demodex overgrowth. Then, they would give a treatment to reduce the number of lash mites on the eyelid and bring it back down to a normal level.

'Sensational' and 'creepy' content

Spiro said the trend of lash mite content is likely because they sound worse than they are.

Lash mites have "a little bit of a special sensational aspect — to know that there's little mites growing on you — it does kind of have that kind of creepy aspect to it.

"But once you realize how ubiquitous and common they are, and how harmless they are, I think it'll die down eventually."

As for self-diagnosing and at-home cleaning, Spiro recommends getting professional advice first.

"It's uncommon to see these things under non magnified events," he urged. "Before taking matters into your own hands, get a proper assessment."

But, he advised people to follow hygienic practices.

"Just make sure your eyelids are clean, [that] any product or makeup is removed before bed, that you're using products that are compatible with your ocular surface."

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