Health

Sunglasses – Part 1

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Head ShotBBy Kevin A. Rogers, OD,
Rogers Regional Eye Center
The real reason to purchase sunglasses is to protect your eyes from the sun. Not only does glare from the sun make it difficult to see, but the UV rays it reflects can cause permanent damage to your eyes and vision. You want to make sure your sunglasses offer optimal protection, fit, comfort and of course, the best possible vision. Here are some things to consider when purchasing your next pair. 
There are two types of UV radiation, UVA and UVB. UVA rays are less intense yet more prevalent than UVB rays, making up 95% of the UV radiation that reaches the surface of the Earth. They have been linked to skin cancer, aging and the development of cataracts. UVB rays are very dangerous to the eyes and are the primary cause of sunburns and cancer. While they are dangerous year round, these rays are more intense during the summer months, especially mid-day between around ten in the morning and four in the afternoon. UVB rays also reflect off of snow, water, sand and concrete. The damage caused by UV rays is irreversible and cumulative, building up over a long period of time. This is why it is important to start wearing sunglasses when you are young (also because your eyes are more sensitive at a younger age). You want to make sure your sunglasses block out 100% of UV rays. This is the most important factor to consider when purchasing your sunglasses. 
Once you are certain your sunglass lenses have the requisite UV protection, you can begin to consider other lens possibilities. Here are some other lens options to consider:
Polarized lenses reduce glare from light reflecting off glass, water, snow, sand or pavement. You should consider polarized lenses if you participate in water or snow sports such as fishing, boating or skiing as the water and snow can create a strong glare. They are also great for comfort while driving by reducing glare and to enhance vision when on the road. 
Certain lens tints enable you to see better or more comfortably under certain circumstances but you have to be careful. Lens tints can distort or reduce vision and some can even harm your vision by increasing your pupil size which leads to an increase of UV radiation penetrating the eye. Look for lenses with a medium tint that keep your eyes comfortable and do not have a negative impact on your vision. Your optometrists’ office can often make specific tint recommendations depending on your lifestyle or particularly activities (ex. golfing vs fishing) and the health of your eyes (for example, cataracts tend to cause more glare). 
Photochromic lenses automatically darken when exposed to UV light. Photochromic lenses are a great option for individuals that wear prescription eyeglasses: one pair can serve you both indoors and outdoors. As soon as you step outside, the lenses will darken, and they’ll reverse when you go back indoors.