You probably know someone who has experienced blindness. Two leading causes of blindness glaucoma and cataracts. Even though contact lens companies may not tell you up front that wearing contact lenses can cause blindness, multiple studies show that contact lenses may be a contributing factor in blindness, especially in developing countries. The World Health Organization (WHO) says that there are over 37 million blind people in the world, and roughly 90 percent of those people reside in developing nations where proper care is easy to practice..

So how can you avoid going blind because of your contact lenses? Follow the following 5 tips and talk to your optometrist about blindness.

1. Practice good hygiene. Good hygiene for you eyeballs? This isn't anything special that you shouldn't already be doing. Good hygiene for you eyes include washing your hands regularly and avoiding touching your eyes with any foreign object including your fingers. You can also wear UV resistant sunglasses to avoid UV radiation. When it comes to contact lens use you'll want to make sure you don't share anything with another contact lens wearer. That includes sharing contact lenses, cleaning solution, eye drops, moisturizers, storage containers and anything else that touches your eye.

2. Replace contacts regularly. Another reason contact lens wearers experience blindness is because they keep their contacts in too long and don't replace them as recommended. If your contacts are designed for single use and are disposable, throw them out after first use. If they're designed to last one month, don't wear them for two months. Another reason is because people leave them in too long. If you keep your contact lenses in for 16 hours every day you may begin to experience additional dryness and irritation. When you no longer need your contacts in, take them out.

3. Eat right. Senior Consultant Ophthalmologist and Rotarian with the Rotary Avoidable Blindness Program, Mr. Low Hong says that the eating right can help improve your eyesight. By eating right Mr. Hong advises eating traffic light-like vegetables. That means those vegetables that are red, green, and yellow. Those colored fruits can contain important chemicals required by the eye to function and have a clearer vision and you'll see colors more clearly. Hong also advises eating carrots because they help improve your eyesight as well.

4. Sleep right. Position is more important that length says Hong when it comes to blindness and cataracts. When you sleep face down on your pillow you put pressure against your eyes and eye sockets that can lead to cataracts and eventually cataract surgery. Additional sleep also helps your eye recover from wearing contact lenses for prolonged periods. Sleep helps your eyes recover from any damage they might have experienced as a result of wearing contacts all day.

5. Avoid eye rubbing. This one may seem simple, but it is often overlooked. If your keep your hands out of your eyes, you're less likely to develop an infection and scratch your cornea. Eye infections are a serious cause of blindness. Another serious cause is inadvertent eye damage usually caused by a foreign object. Stay aware when walking near trees with low hanging branches and whenever around objects that are hanging at eye level.

Blindness is serious and extremely difficult to treat. If you take precaution and recognize how valuable and fragile your eyes are, they'll hopefully last you an entire lifetime!