Every kid grows up in a house with one cardinal rule that is chief among the others.

"Always make your bed," or "Do unto others," for example.

As the daughter of an optometrist, the cardinal rule in our house was “Never sleep in your contacts."

While this may seem like a strange rule for my family, my brother and I both have been wearing soft contact lenses since the age of ten, so it made sense. Since the age of ten, I've had two decades of adhering to our family's “cardinal rule."

Despite the very scary and real health consequences of sleeping in contact lenses (disease, pain, blindness), 99% of respondents in a Centers for Disease Control reportexhibited some form of “risky eye care behavior," and 50% reported sleeping in their lenses on a regular basis!

This is not only a bad habit but a vision-threatening one that I'm about to bust right now.

What about lenses approved for extended wear?

Yes, some contact lenses are approved for extended wear, including during sleep. But, that doesn't mean you should.

Research from the CDC finds those who wear contacts overnight (yes, even ones approved for extended use) are six to eight times more likely to experience a contact lens-related complication or infection.

“While many contacts are approved for overnight wear, the habit of sleeping in contact lenses is not without risk," says Ernest Bowling, O.D., a nationally recognized optometrist. “The chances of serious eye infection are greatly increased with overnight contact lens wear."

Even if you're wearing a contact lens approved for up to 30 days continuous wear, most eye doctors recommend taking them out overnight at least once each week. Plus, you have to be religious about throwing them out after 30 days and should be seeing your doctor every six months to keep infections at bay.

Yeah yeah, but is it bad to sleep with contacts in? Let's get real.

If you've ever wondered can you sleep with contacts, the answer is no! You really shouldn't. When you close your eyes to sleep with your contacts in, you're enclosing your lenses in the perfect environment for bacteria to grow.

Lenses need oxygen to breathe. It keeps our corneas healthy and happy.

When you close your eyes, you not only stop the oxygen flow, but you can trap bacteria on the top of the lens. Keeping your eyes closed for many hours (like during sleep) allows bacteria to grow in the warm, moist, dark cave of your eye socket. This type of environment incubates bacteria better than any other, so sleeping with your contacts is, in short, a really bad idea.

What are some of the risks associated with sleeping in contact lenses?

The most serious side effect of sleeping with contacts is vision loss, which makes being too lazy to take your contacts out seem like a lame excuse.

On the less catastrophic scale, sleeping with contacts can lead to eye infections, red eye, light sensitivity, corneal ulcers and the inability to wear contacts. Several people in the CDC report needed emergency corneal transplants just to save their vision; one man experienced major issues after wearing his contacts continuously for two days while on a hunting trip!

I'm not trying to scare you. There was a time (or two) in college where I fell asleep in my lenses after a night out. For those who do this, it's important to let your eyes have some oxygen, re-wet the lenses with drops, wash your hands and take your lenses out soon after waking.Then, wear your glasses for the rest of the day to let your eyes relax.

Just don't make a regular habit of sleeping in contacts — ever — and practice good lens hygiene to prevent infection too.

Also, don't tell my Dad I told you what to do if you sleep with your lenses in. It's a cardinal rule in our house, after all. ?