Imagine that your camera lens has a fingerprint smudge and you take a picture of the scenery on a clear summer day. When you look back at the photo you took, the light will likely overpower the photo and the image that was once clear may look cloudy on your screen. Your eyes work in a similar fashion — the lens must be clear in order to reveal sharp, crisp images.
The clouding of the lens in your eye is called a cataract and it causes vision that was once clear to become a little cloudy. The lens is a clear part that rests behind your iris and pupil and helps to focus an image or light on the retina, which changes the light into nerve signals for the brain.
According to the National Eye Institute, the lens is made of mostly water and protein that is packed in a precise way that allows light to pass through the lens and keeps it clear. Over time, though, the protein may clump together and form a cloudy cataract on the lens. As it grows, it clouds more of the lens and makes vision blurry. If the lens is clouded from a cataract, you may experience some or all of the common symptoms, which include clouded vision, double vision, the fading of colors, light sensitivity or poor night vision.
>> Read more: Seeing Spots: When to Be Concerned
Most cataracts are caused by aging. They can begin to develop in your 40s or 50s but, during this time, they are often unobtrusive to your vision. After age 60, most cataracts begin to affect your ability to see clearly. Researchers believe that the protein in your lens clumps due to the constant strain we put on our eyes, but have found that other health risks, such as diabetes and smoking, can contribute to the formation of secondary cataracts. Other less common types of cataracts include traumatic cataracts caused by eye injury, congenial cataracts that are present at birth or develop in the eyes of young children, or radiation cataracts that are caused by exposure to some types of radiation. (via National Eye Institute)
No matter the cause, Prevent Blindness reports that nearly 24 million Americans over age 40 have a cataract and that 30 million will experience cataracts in their eyes by 2020. It is the leading cause of blindness worldwide.
How to Protect Your Vision
As researchers suspect that cataracts that develop with age are caused by your lens' protein wearing down, it is important to maintain habits that support eye health as you approach age 40. Eating foods rich with antioxidants like leafy vegetables and fruits may reduce the risk of cataracts, and wearing sunglasses and a sun-blocking brimmed hat may delay the protein's wear. Since smoking is also related to the development of cataracts, stop lighting up if you smoke. After age 60, you should visit the optometrist for a comprehensive dilated eye exam at least every two years. This may allow for the early treatment of any eye-related health issues and keep you seeing clearly.
If cataracts are detected early, your vision may be improved by trying new glasses, magnifiers or anti-glare glasses coatings. To permanently remove the clouds, surgery is necessary to replace your cloudy lens with a clear, artificial one. This decision should be considered only when other treatments have been tried or when you experience other eye-related issues.