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What’s the science behind lens care and wear? 

Contact lens wearers will be all too familiar with the dos and don’ts of lens care and wear. But have you ever wondered why you shouldn’t sleep in your contacts? And why using the right solution really matters? Our in-house optometrist, Roshni, reveals all. 

1. Why shouldn’t I sleep in my contacts?

Our eyes need oxygen to fight infections and stay healthy. When we’re awake, blinking keeps our eyes moist and allows oxygen to flow freely. But when our eyes are closed, the cornea receives less oxygen. 

While modern lenses are more breathable than ever, sleeping in contacts adds an extra barrier for oxygen to reach the cornea. Besides the eyes becoming dry, it can cause the cornea to swell, making it susceptible to infection. A good rule of thumb is to remove your lenses at the end of your workday. That way, you’re less likely to fall asleep in them. 

Some types of reusable lenses are approved for overnight wear a great option if you’re prone to taking naps in contacts. Extended wear lenses are not suitable for everyone, so be sure to speak to your optician before switching. 

2. Why is it a good idea to insert my contacts before applying makeup?

First of all, applying makeup is fiddly business, so you’ll want to get a good look at what you’re doing. Secondly, putting your lenses in before applying your makeup means you’re less likely to transfer cosmetics from your hands to your lenses. Getting makeup particles lodged underneath your lens is uncomfortable, and can even cause infection. 

When removing your makeup, just do it in reverse. Take out your lenses before removing your makeup. Easy. 

3. Can I extend the life of my monthly lenses?

For money-saving reasons, it might be tempting to stretch the life of your lenses. But wearing contacts past their prime can lead to discomfort and infection. 

Over time, protein deposits and allergens build up on the surface of your lenses. While cleaning your contacts helps to prevent this, lens solution doesn’t remove 100% of deposits. 

Additionally, when the lens exceeds its lifespan, the built-in pathways that allow oxygen to flow will start to break down. Without enough oxygen, the eyes can become sore and dry. To get the most out of your lenses, and to enjoy clear and comfy vision, it’s important to stick the recommended replacement schedule. 

4. Why isn’t it safe to reuse lens solution?

Reusing or ‘topping off’ lens solution dilutes its disinfecting power, which could leave you at risk for an eye infection. Contacts collect dirt and debris throughout the day, some of which ends up in your solution. If you reuse the same solution, you’re likely to contaminate your lenses every time you store them. If you don’t want the hassle of solutions, daily disposables are a convenient, fuss-free alternative. 

5. Why do I need to clean and replace my lens case? 

You wouldn’t put clean clothes into a dirty suitcase, would you? Similarly, you wouldn’t want to store your clean contacts in a dirty lens case overnight. Cleaning your case out after every use avoids bacteria build-up on the lens and reduces the risk of infection.

It’s a quick and easy process. Simply discard the old solution and then rinse and refill the case with fresh solution. Remember, you’ll want to replace your case every 2-3 months, even if it looks like it’s in tip-top condition. 

6. Why can daily disposables only be used once?

The beauty of daily disposables is that you can simply bin the lens at the end of a full day’s wear, without the hassle of cleaning or buying solutions. 

Since dailies are designed for one-time use, the material isn’t resistant to deposit build-up and continued wear. If you try to reuse them, the surface starts to break down, and dirt and debris can become trapped within the lens, leaving you prone to infection. By tossing your dailies out after each use, you can easily maintain clear, comfy and healthy eyes.

7. Why can’t I clean my lenses with water? 

Water might seem clean, but it carries all sorts of nasty impurities that can contaminate your contacts and cause infection. Water can also cause lenses to change shape, swell and stick to the eyes, which is uncomfy and can scratch the cornea. 

Even purified bottled water can contain bacteria. Keep it clean by using the appropriate cleaning, storing and disinfecting solutions on your lenses. 

8. Why shouldn’t I flush my lenses down the toilet? 

Contact lenses are made with plastic, so flushing them down the toilet can contribute to the pollution of marine environments. 

The good news is that lens manufacturers are continually evolving their processes to make more materials recyclable. Nowadays, soft lenses, blister packs, cardboard packaging and lens cases can all be recycled using a local scheme. Contact lenses themselves are too small for household recycling. If you don’t have access to a local recycling scheme, the best thing you can do is to throw your lenses in the bin. 

Final thoughts?

Contacts give us the freedom and flexibility to enjoy the things we love without wearing specs. Like most things, they come with their own set of guidelines, but it’s these simple tips that help us get the most out of our lenses. You’ll find more helpful advice on taking care of your lenses over on our Vision Hub.