Just as the sun can damage your skin, so its harsh rays can damage your eyes.
Ultraviolet light from the sun does more than damage your skin. Ultraviolet (UV) light can penetrate the lens (front of the eye) damaging both this structure and the retina - the region at the back of the eye that is directly responsible for vision.
Although eyecare professionals have known for many years that long-term exposure to sunlight causes the vision to become impaired, the reason why has only recently been understood.
Ongoing research into the effects of UV light and blue light has shown that these components of sunshine contribute to a number of eye disorders including cataract, macular degeneration, and sunburn of the cornea (photokeratitis).
UV Light and CataractsA cataract is the name given to a cloudiness that develops in the lens of the eye over time. If left untreated, the condition can cause partial blindness.
The lens consists mostly of protein and water. The protein is bonded together in a very precise order that keeps the lens clear and allows light to pass through it. A cataract forms when the structure of the protein molecules degenerates, causing them to clump together. This damage impairs the passage of light, causing cloudy and dull vision.
Since cataracts develop over time, they have traditionally been regarded as a natural part of the aging process. Recent research strongly suggests, however, that UV light plays a key role in the development of cataracts. Significantly, areas of the world that receive more sunshine have a greater incidence of cataracts¹.
Scientists believe that UV light penetrating the skin or the eyes creates free radicals. These highly unstable molecules cause damage to the body’s tissues, including the proteins that form the lens of the eye.
UV Light and Macular DegenerationAge-related macular degeneration (AMD) is the leading cause of blindness among older Canadians. Unlike cataracts, which can be surgically treated to restore vision, no such remedy exists for AMD. It is therefore extremely important to understand the causes of the condition and what can be done to prevent or arrest its development.
AMD is a degenerative condition of the macula, a small region in the centre of the retina that allows us to see in detail. This precise vision is essential for activities such as driving, facial recognition, reading, painting, sewing, knitting and other hobbies or crafts.
The most likely cause of AMD is hardening of the arteries that nourish the retina. This reduces blood flow and deprives the retinal tissue of the oxygen and nutrients required to function properly.
Several factors are believed to contribute towards hardening of the retinal arteries and AMD. These include genetics, diet and free radical action caused by exposure to sunlight.
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One of the many miracles of the human body is its ability to repair or replace cells that have been damaged. Cells of the skin, for example, are constantly in the process of developing, moving to the surface, then sloughing off, ensuring that older, damaged cells are replaced. In almost every part of your body, the story of replacement and repair is repeated - except for the lens of the eye. The cells of the lens are never replaced. This means that damage to the lens accumulates throughout life. |
UV Light and Photokeratitis/GlarePhotokeratitis is sunburn of the cornea caused by overexposure to UV light. The painful condition almost always results from being out of doors on a bright, sunny day, without adequate eye protection. Snowblindness is a form of photokeratitis, caused by the reflection of sun bouncing off the snow and entering the unprotected eye. Long-term exposure to this type of glare can lead to extreme eye fatigue and may also degrade night vision.
Even the glare bouncing off objects on a bright day can present dangers to the eyes and to you. Many a driving accident has taken place when squinting or blocking glare with the hand or a newspaper has resulted in limitation of vision.
Sunglasses with polarization will eliminate glare and help keep your eyes comfortable when out of doors in bright light.
Protecting Your EyesThe regular use of sunglasses with full-spectrum UVA/UVB protection will help prevent your eyes from sustaining damage that could harm your vision. You will find a variety of sunglasses offering full-spectrum UV protection at London Drugs. These include Suntech Optics sunglasses and Solar Shield® Fits Over™ sunglasses for use alone or over prescription glasses. With flexible temples to ensure a customized fit, Fits Over™ sunglasses come in several sizes to fit over all prescription frames. Solar Shield® Fits Over™ clip-ons are also available for people who prefer this type of eye protection.
If You've Had Eye SurgeryIf you have recently had eye surgery, your eyes will be extra sensitive. To protect your eyes from glare and associated UV damage, your eye surgeon will likely recommend that you wear full-spectrum sunglasses on their own or sunglasses that fit over your prescription lenses. Solar Shield® Fits Over™ sunglasses are ideal for this purpose.
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Assessing Your Risk Everyone is at risk for sunlight-related eye disorders and damage from UV radiation. If you fall into one of the categories listed below, your risk is increased.
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People taking certain medications such as birth control or antibiotics
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Children and seniors
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Contact lens wearers
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Outdoor enthusiasts
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Refractive/cataract surgery patients
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People with light-coloured eyes or who are light-sensitive
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People living at higher altitudes or close to the Equator
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People who regularly experience high-glare conditions such as when commuting on bright or sunny days.
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1. Heck, D.E., Gerecke, D.R., et al., Solar ultraviolet radiation as a trigger of cell signal transduction. Toxicol. Appl. Pharmacol. 2004 Mar 15; 195(3): 288-97