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Contact Lenses Fill Your Eyes With Skin-Like Bacteria
Getty Images; Illustration by Lauren Margit Jones for TIME

You Asked: What Type of Contact Lenses Should I Wear?

Jul 06, 2017
TIME Health
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If you’re used to keeping a pair of contacts for two weeks or a month, the concept of daily disposable contacts can seem almost profligate—like throwing away your underwear at night and unwrapping a new pair in the morning.

It’s true that in most cases, daily disposables are more expensive. Even factoring in the money you’d save on contact cleaning solution, you’re probably going to pay more for dailies than you would for longer-use contacts. Some are two to three times more expensive than extended-wear lenses.

But setting aside the added cost and excess packaging (a concern for those trying to reduce waste), the benefits of daily disposables are numerous.

Anyone who has worn longer-use contacts knows they tend to feel itchy and uncomfortable toward the end of their two-week or 30-day lifespan. “As you wear them, there’s a gradual build-up of lipids and proteins and other things that come from your eyes and tears,” says Dr. Stephen Anesi, an ophthalmologist in private practice at Massachusetts Eye Research and Surgery Institute.

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Your eyes may also encounter airborne allergens that can hitch a ride to your lenses. Even if you’re rinsing and disinfecting them regularly, cleaning your lenses doesn’t remove 100% of the gunk that accumulates. “There’s always some residual stuff there, and that can cause irritation, especially for people with allergies,”Anesi says. With daily disposables, “you’re opening a fresh pair of sterile lenses every morning."

Discomfort isn’t the only risk of that accumulated gunk.

When contact lenses are improperly cleaned or maintained—maybe you forget to wash your hands before touching them, or you let your contact case get a little grimy—bacteria can proliferate. “Bacteria on the lens comes into contact with the cornea, and it can grow there and cause a serious infection,” says Dr. Bennie Jeng, chair of ophthalmology at the University of Maryland School of Medicine.

MORE: Contact Lenses Fill Your Eyes With Bacteria

In 2010, Jeng coauthored a study on ulcerative keratitis, a kind of eye infection that leads to inflammation and pain. In some cases, this and other contact lens-related infections can cause permanent vision changes or even blindness, he says. Since daily disposables remove a lot of room for maintenance-related operator error, they’re less likely to produce infections.

If you’re good about removing your extended-use contacts at night and following proper protocol when it comes to cleaning and storing them, your risk for infection isn’t high. But the FDA has approved some contact lenses for overnight wear, and Anesi says many people see that as a green light to let days pass without removing their contacts. That’s bad news. “You’re supposed to be able to wear lenses at night without cleaning them, but most eye care professionals like me who know what kinds of things can happen don’t recommend that,” he says. “Our eyes are not built to wear contacts, so you have to respect that.”

Apart from infections, overuse can also lead to a kind of chronic irritation. “People can develop almost like an allergy to the contact lens, where they have an inability to wear anything in their eye at all,” Anesi says.

MORE: You're Treating Pink Eye The Wrong Way

If switching to daily disposables means you’ll stop wearing your lenses overnight—or will wear them less in general—that’s a good thing. “I see infections every day, so I may be biased,” Jeng says. “But in my opinion, for convenience and safety, I recommend daily disposables.”

Anesi echoes this take, but says the choice really depends on the individual and his or her lens habits. Some people, due to the nature of their work or lifestyle, may like the flexibility of being able to take out and store their contacts whenever they feel like it. (Considering the cost of daily disposables, you may feel like you’re wasting them by not wearing them all day long.)

“Bi-weeklies or monthlies are fine and work well as long as you properly maintain them,” Anesi adds. “But if you don’t want to clean them, or you’re prone to allergies or problems related to your contacts, then daily disposables offer a lot of benefits.”

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